# GCN_circulars

GRB_name: GRB231018A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34847
SUBJECT: GRB 231018A: Glowbug gamma-ray detection
DATE:    23/10/19 21:07:59 GMT
FROM:    C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>

C.C. Cheung, M. Kerr, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:
 
The Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 231018A, which was also detected by Fermi/GBM, Konus-Wind, CALET, GECAM-B, INTEGRAL/SPI-ACS, and Swift/BAT, resulting in an IPN localization (GCN 34826, 34845, 34846).
 
Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-10-18 12:30:07.824 with a duration of 87.6 s and a total significance of about 159 sigma.  The Glowbug light curve comprises multiple peaks and is generally similar to the Konus-Wind light curve (GCN 34846).
 
Using a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=1.0 and a cutoff energy ("Epeak") of 193 keV.  The modeled 10-10000 keV fluence is 3.4e-05 erg/cm^2.
 
The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.
 
Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC.  It was launched on 2023 March 15 aboard the Department of Defense Space Test Programâ€™s STP-H9 to the ISS.  The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.
 
[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006
 
Distribution Statement A: Approved for public release.  Distribution is unlimited.


GRB_name: GRB231019A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34848
SUBJECT: Fermi GRB 231019A: Global MASTER-Net observations report
DATE:    23/10/20 00:00:57 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-Amur robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB 231019A ( Fermi GBM team, GCN 34842) errorbox  816 sec after notice time and 850 sec after trigger time at 2023-10-19 17:24:09 UT, with upper limit up to  17.5 mag. The observations began at zenith distance = 46 deg. The sun  altitude  is -42.0 deg. 

The galactic latitude b = -12 deg., longitude l = 103 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2288694

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

     881 | 2023-10-19 17:24:09 |         MASTER-Amur | (22h 54m 16.71s , +46d 46m 10.5s) |   C |    60 | 17.4 |        
     961 | 2023-10-19 17:25:28 |         MASTER-Amur | (23h 05m 59.53s , +46d 44m 56.9s) |   C |    60 | 17.5 |        
    1040 | 2023-10-19 17:26:48 |         MASTER-Amur | (22h 59m 27.09s , +48d 37m 55.9s) |   C |    60 | 17.5 |        
    1120 | 2023-10-19 17:28:08 |         MASTER-Amur | (23h 11m 28.93s , +48d 39m 20.4s) |   C |    60 | 17.4 |        
    1200 | 2023-10-19 17:29:28 |         MASTER-Amur | (22h 36m 34.03s , +48d 40m 14.4s) |   C |    60 | 17.1 |        
    1279 | 2023-10-19 17:30:47 |         MASTER-Amur | (22h 48m 32.17s , +48d 39m 03.7s) |   C |    60 | 17.4 |        
    1370 | 2023-10-19 17:32:18 |         MASTER-Amur | (22h 42m 41.86s , +50d 33m 03.9s) |   C |    60 | 17.2 |        
    1450 | 2023-10-19 17:33:38 |         MASTER-Amur | (22h 55m 09.57s , +50d 31m 51.8s) |   C |    60 | 17.4 |        
    1530 | 2023-10-19 17:34:58 |         MASTER-Amur | (22h 54m 23.63s , +46d 44m 22.5s) |   C |    60 | 17.1 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB231018A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34849
SUBJECT: GRB 231018A: CALET Gamma-Ray Burst Monitor detection
DATE:    23/10/20 04:35:30 GMT
FROM:    Yuta Kawakubo at Louisiana State University <kawakubo1@lsu.edu>

P. S. Marrocchesi (U of Siena), A. Yoshida, T. Sakamoto,
S. Sugita (AGU), Y. Kawakubo (LSU), K. Yamaoka (Nagoya U),
S. Nakahira (JAXA), Y. Asaoka (ICRR), S. Torii, Y. Akaike, 
K. Kobayashi (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU), 
S. Ricciarini (U of Florence),
and the CALET collaboration:

The long GRB 231018A (Fermi GBM Final Real-time Localization: Fermi
GBM team, GCN Circ. 34826; BALROG localization: Preis et al., 
GCN Circ 34827; Fermi GBM Detection: Lesage et al., GCN Circ 34831;
IPN triangulation: Svinkin et al., GCN Circ 34845; Konus-Wind detection: 
Frederiks et al., GCN Circ 34846; Glowbug gamma-ray detection: Cheung 
et al., GCN Circ 34847) triggered the CALET Gamma-ray Burst Monitor (CGBM) 
at 12:30:52.87 UTC on 18 October 2023
(http://cgbm.calet.jp/cgbm_trigger/flight/1381667434/index.html).
The burst signal was seen by only the SGM detector.

The burst light curve shows a multi-peaked structure that ends T+46 sec.
Since CGBM was in the HV-on sequence, the whole episode was not observed by CGBM.
The ground-processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1381667434/

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at Waseda University.


GRB_name: GRB231018A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34850
SUBJECT: GRB 231018A: GRBAlpha detection
DATE:    23/10/20 10:02:38 GMT
FROM:    Marianna DafÄÃ­kovÃ¡ at Masaryk University <500025@mail.muni.cz>

M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal,  A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), yyT. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory),  T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.

The long-duration GRB 231018A (Fermi/GBM detection: GCN 34831; Konus/Wind detection: GCN 34846; Glowbug detection: GCN 34847; CALET/CGBM detection: GCN 34849; INTEGRAL/SPI-ACS peak detection at 2023-10-18 ~12:31:08 UT) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023, A&A, 677, 40; arXiv:2302.10048).

The detection was confirmed at the peak time 2023-10-18 12:31:08 UTC. The T90 duration measured by GRBAlpha is 32 s and the overall significance during T90 reaches 91 sigma.

The light curve obtained by GRBAlpha is available here: 
https://grbalpha.konkoly.hu/static/share/GRB231018A_GCN.pdf

All GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ 
GRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume. 


GRB_name: GRB231017A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34853
SUBJECT: GRB 231017A: 1.3m DFOT Optical upper limit
DATE:    23/10/20 17:12:08 GMT
FROM:    Amit Kumar Ror at ARIES <mitturor77894@gmail.com>

Amit K. Ror, Rahul Gupta, Amar Aryan, Shashi B. Pandey, Rishi C., and
Neelam Panwar (ARIES) report:

We observed the field of Fermi, and Swift detected GRB 231017A (Fermi GCM
Team GCN 34822; Mangan et al. 2023, GCN 34830; DeLaunay et al. 2023, GCN
34824; and Swift team GCN 34825) with the 1.3m Devasthal Fast Optical
Telescope (DFOT), located at the Devasthal Observatory of the Aryabhatta
Research Institute of Observational Sciences (ARIES), India. The
observations were started on 2023-10-18 at 22:19:07 UT, i.e., ~ 1.6 days
after the GBM trigger. We have taken multiple frames with an exposure time
of 100 s in the R filter. We stacked the images after the alignment. We did
not detect any optical afterglow in our stacked image within the error box
of Swift-XRT observation (Dichiara et al., 2023, GCN 34829). We obtain the
following preliminary 3-sigma upper limit in the stacked image:


Date Start_UT T_start-T0 (days) Filter  Exp time (s)  Limiting magnitude

=========================================================

2023-10-18 22:19:07     1.6     R     100*36     > 21.6

Our non-detection is consistent with Kumar et al. 2023, GCN 34833;
Strausbaugh et al. 2023, GCN 34834; Shrestha et al. 2023, GCN 34836; Xu et
al. 2023, GCN 34840; and Belkin et al. 2023, GCN 34841.

The magnitude is not corrected for the Galactic extinction in the direction
of the burst. Photometric calibration is performed using the standard stars
from the USNO-B1.0 catalog. This circular may be cited.


GRB_name: GRB231012A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34855
SUBJECT: GRB 231012A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
DATE:    23/10/20 18:43:55 GMT
FROM:    Tomas Fernando Ahumada Mena at Caltech <tahumada@umd.edu>

Tomas Ahumada (CIT), Vishwajeet Swain (IITB), Anirudh Salgundi (IITB), Viraj Karambelkar (CIT), Gaurav Waratkar (IITB), Ravi Kumar (IITB), Robert Stein (CIT), Theophile du Laz (CIT), Igor Andreoni (UMD), Michael Coughlin (UMN), Mansi Kasliwal (CIT), Simeon Reusch (DESY), Jannis Necker (DESY), Shreya Anand (CIT), report on behalf of the ZTF collaboration:

We observed the localization region of the short GRB 231012A (trigger 718781545, GCN 34813) detected by the Gamma-Ray Burst Monitor (GBM) on the Fermi satellite with the Palomar 48 inch telescope equipped with the 47 square degree Zwicky Transient Facility (ZTF) camera. We obtained a series of g- and r-band images covering 410 square degrees beginning at 2023-10-12T07:24:37.002 (1.9 hours after the burst trigger time). This corresponds to 59% of the probability enclosed in the Earth-occultation corrected GRB localization map. Each exposure was 300 seconds, reaching g-band and r-band median depths of 21.5 mag and 21.0 mag respectively. As part of this trigger, we covered 76% of the IPN localization region, starting 2023-10-12T07:40:11.003 (2.1 hours after the burst). 

The images were processed in real-time through the ZTF reduction and image subtraction pipelines at IPAC (Masci et al. 2019).

We queried the ZTF alert stream using Kowalski (Duev et al. 2019) through Fritz (Coughlin et al. 2023) and AMPEL (Nordin et al. 2019). We required at least 2 detections separated by at least 15 minutes to select against moving objects. Furthermore, we cross-match our candidates with the Minor Planet Center to flag known asteroids, reject stellar sources (Tachibana and Miller 2018), and apply machine learning algorithms (Mahabal et al. 2019). We require that no spatially coincident ZTF alerts were issued before the detection time of the GBM trigger. 

Six ZTF sources were time and spatially coincident with the burst, although none showed a rapid evolution. 

ZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA, WIS, Israel; OKC, Sweden; JSI/UMd, USA; U Washington, USA; DESY,
Germany; MOST, Taiwan; UW Milwaukee, USA; LANL USA; Tokyo Tech, Japan; IITB, India; IIA, India; LJMU, UK; TTU, USA; SDSU, USA and USyd, Australia.
ZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341.
GROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949.
Alert distribution service provided by DIRAC@UW (Patterson et al. 2019).
Alert database searches are done by AMPEL (Nordin et al. 2019) and Kowalski (Duev et al. 2019). GROWTH India telescope is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA). GROWTH-India project is supported by SERB and administered by IUSSTF, under grant number IUSSTF/PIRE Program/GROWTH/2015-16 and IUCAA.
    


GRB_name: GRB231020A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34856
SUBJECT: GRB 231020A: Fermi GBM Final Real-time Localization
DATE:    23/10/20 19:04:32 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 18:56:58 UT on 20 Oct 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231020A (trigger 719521023.300322 / 231020790).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 317.5, Dec = -28.7 (J2000 degrees, equivalent to J2000 21h 10m, -28d 41'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 87.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231020790/quicklook/glg_skymap_all_bn231020790.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231020790/quicklook/glg_healpix_all_bn231020790.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231020790/quicklook/glg_lc_medres34_bn231020790.gif


GRB_name: GRB231020A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34858
SUBJECT: Fermi GRB 231020A: Global MASTER-Net observations report
DATE:    23/10/20 19:30:48 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-Kislovodsk robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB 231020A ( Fermi GBM team, GCN 34856) errorbox  510 sec after notice time and 519 sec after trigger time at 2023-10-20 19:05:37 UT, with upper limit up to  16.7 mag. The observations began at zenith distance = 80 deg. The sun  altitude  is -49.5 deg. 

The galactic latitude b = -42 deg., longitude l = 18 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2289661

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

     569 | 2023-10-20 19:05:37 |   MASTER-Kislovodsk | (21h 11m 20.75s , -28d 16m 42.1s) |  P| |   100 | 16.5 |        
     705 | 2023-10-20 19:07:37 |   MASTER-Kislovodsk | (21h 11m 26.12s , -28d 17m 47.5s) |  P| |   130 | 16.7 |        
     870 | 2023-10-20 19:10:08 |   MASTER-Kislovodsk | (21h 11m 20.36s , -28d 18m 56.3s) |  P| |   160 | 16.7 |        


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB231015A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34859
SUBJECT: GRB 231015A: NuSTAR Detection of Prompt Emission
DATE:    23/10/20 19:34:41 GMT
FROM:    Brian Grefenstette at Caltech/NuSTAR <bwgref@srl.caltech.edu>

B. Grefenstette reports on behalf of the NuSTAR Search for INteresting Gamma-ray Signals (SINGS) working group:

The NuSTAR SINGS working group reports the discovery of prompt emission from a potential GRB 231015A in the NuSTAR CsI anti-coincidence shields. This GRB was identified through a blind search using the CsI shield rates. Details of the search algorithm will be described in a future paper. 

The CsI data are recorded at 1 Hz and show a broad burst with multiple peaks. The initial NuSTAR trigger had a trigger time of 2023-10-15T23:49:35, which is one the rising edge of the slow, initial peak and is consistent with the onset time reported by GlowBug (Cheung et al, GCN Circ 3485). A stronger second peak is also seen, consistent with the strongest peak identified in the AstroSat data (2023-10-15T23:49:53, Waratkar et al, GCN Circ 3482).

The stronger second burst resulted in peak 1-sec count rates of ~3,000 counts per second in both the FPMA and FPMB shield units. Typical background rates are ~1,000 counts per second. The peak of the second burst is unresolved (e.g., shorter than the 1-s bins) with a decay back to quiescence of ~5-s. The first peak had a rise time of ~10-s and a longer overall duration.

The burst was detected in both the CdZnTe detectors. We see some emission associated with multiple peaks during the burst above 40 keV, though the number of counts is relatively modest (~10s of counts above 40 keV) so that more detailed analysis is limited by counting statistics.

The automated light curve report for this GRB, discovery report, off-line analysis of the shield data, and the CdZnTe lightcurves can be found here:

https://nustarsoc.caltech.edu/NuSTAR_Public/grbs/reports/2023/231015A/

Information on NuSTAR SINGS can be found here: 

https://nustarsoc.caltech.edu/NuSTAR_Public/grbs/

NuSTAR is a NASA Small Explorer mission led by Caltech and managed by JPL for NASAâ€™s Science Mission Directorate in Washington. 


GRB_name: GRB231020A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34861
SUBJECT: GRB 231020A: BALROG localization (Fermi Trigger  / GRB 231020790)
DATE:    23/10/20 21:23:35 GMT
FROM:    Jochen Greiner at MPE <jcgrog@mpe.mpg.de>

T. Preis, B. Biltzinger,  J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
 at 18:56:58 on 20 Oct. 2023 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 316.0+/-0.4 deg
Decl.(2000.0) = -31.3+/-0.3 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB231020790/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB231020790/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB231020790/json

                        


GRB_name: GRB231020B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34862
SUBJECT: GRB 231020B: Fermi GBM Final Real-time Localization
DATE:    23/10/20 21:46:18 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 21:35:52 UT on 20 Oct 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231020B (trigger 719530557.906538 / 231020900).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 221.4, Dec = 15.6 (J2000 degrees, equivalent to J2000 14h 45m, 15d 35'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 98.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231020900/quicklook/glg_skymap_all_bn231020900.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231020900/quicklook/glg_healpix_all_bn231020900.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231020900/quicklook/glg_lc_medres34_bn231020900.gif


GRB_name: GRB231020B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34864
SUBJECT: GRB 231020B: BALROG localization (Fermi Trigger 719530557 / GRB 231020900)
DATE:    23/10/21 07:02:45 GMT
FROM:    Jochen Greiner at MPE <jcgrog@mpe.mpg.de>

T. Preis, B. Biltzinger, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
719530557 at 21:35:52 on 20 Oct. 2023 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 221.6+/-0.4 deg
Decl.(2000.0) = 17.6+/-0.6 deg
We estimate an additional systematic error of 1 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB231020900/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB231020900/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB231020900/json

                        


GRB_name: GRB231018A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34865
SUBJECT: GRB 231018A: VZLUSAT-2 detection
DATE:    23/10/21 09:42:35 GMT
FROM:    Marianna DafÄÃ­kovÃ¡ at Masaryk University <500025@mail.muni.cz>

M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory),  N. Werner  (Masaryk U.), M. Ohno (Hiroshima U.),  L. Meszaros, B. Csak (Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory),  T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU)  -- the VZLUSAT-2/GRB payload collaboration.

The long duration GRB 231018A (Fermi/GBM detection: GCN 34831; Konus/Wind detection: GCN 34846; Glowbug detection: GCN 34847; CALET/CGBM detection: GCN 34849; GRBAlpha detection: GCN 34850; INTEGRAL/SPI-ACS peak detection at 2023-10-18 ~12:31:08 UT) was detected by the GRB detector on board of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).

The data acquisition was performed by the GRB detector unit no. 1. The detection was confirmed at the peak time 2023-10-18 12:31:10 UTC. The T90 duration is 41 s and the significance during T90 reaches 25 sigma.

The light curve obtained by VZLUSAT-2 is available here:
https://vzlusat2.konkoly.hu/static/share/GRB231018A_GCN_VZLUSAT2.pdf

All VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/
The GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral.


GRB_name: GRB231019A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34866
SUBJECT: GRB 231019A: VZLUSAT-2 detection
DATE:    23/10/21 09:56:25 GMT
FROM:    Marianna DafÄÃ­kovÃ¡ at Masaryk University <500025@mail.muni.cz>

M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory),  N. Werner  (Masaryk U.), M. Ohno (Hiroshima U.),  L. Meszaros, B. Csak (Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory),  T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU)  -- the VZLUSAT-2/GRB payload collaboration.

The long duration GRB 231019A (Fermi/GBM detection: GCN 34842; INTEGRAL/SPI-ACS peak detection at 2023-10-19 ~17:09:58 UT) was detected by the GRB detectors on board of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).

The data acquisition was performed by the GRB detector units no. 0 and no. 1. The detection was confirmed at the peak time 2023-10-19 17:10:01 UTC. The T90 duration is 10 s (6 s) and the significance during T90 reaches 5.5 sigma (4.6 sigma) for detector unit no. 0 (no. 1).

The light curve obtained by VZLUSAT-2 is available here:
https://vzlusat2.konkoly.hu/static/share/GRB231019A_GCN_VZLUSAT2.pdf

All VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/
The GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral.


GRB_name: GRB231017A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34867
SUBJECT: GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
DATE:    23/10/21 11:22:19 GMT
FROM:    XXXX at IKI <alex@cgrsmx.iki.rssi.ru>

S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), N. Pankov (HSE) report on behalf of GRB IKI FuN:

We observed the field of GBM/Fermi and Swift/BAT-GUANO candidate of GRB 231017A (Fermi GCM Team GCN 34822; Mangan et al. 2023, GCN 34830; DeLaunay et al. 2023, GCN 34824; GCN 34825)  with AZT-33IK telescope of Mondy observatory  in  R-filter on 2023-10-20 starting (UT) 18:02:43. We detect only one object within Swift-XRT X2 candidate error circle (Dichiara et al. GCN 34829) at coordinates of (J2000)  05:44:40.6245 +56:44:54.767. The object position is 5.3 arcsec apart from  Swift-XRT center of the XRT X2 error circle. However, at the moment we cannot say about the variability of the object. 
We may propose the object as a candidate for an afterglow or host galaxy of GRB 230420A. 

Preliminary photometry  of the object is following

Date       UT start  t-T0     Exp.  Filter   OT     Err.  UL(3sigma)
                   (mid, days)  (s)
2023-10-20 18:02:43  3.43519  29x120 R       22.98  0.20   23.5

The photometry is based on nearby USNO-B1.0 R2 stars
USNO-B1.0
RA DEC R2
05:44:36.1893600 +56:44:30.523200 15.96
05:44:49.0394400 +56:45:26.060400 16.24
05:44:55.8448800 +56:45:12.002400 16.30
05:44:44.9767200 +56:47:48.480000 16.48


GRB_name: GRB231004A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34868
SUBJECT: GRID detection of GRB 231004A
DATE:    23/10/21 13:16:40 GMT
FROM:    GRID Student Team at Tsinghua University <grid@tsinghua.edu.cn>

Chenyu Wang and Zirui Yang report on behalf of the GRID Collaboration:

The long-duration GRB 231004A (Fermi/GBM detection: GCN Circular 34795, IceCube detection: GCN Circular 34797, CALET detection: GCN Circular 34804, Glowbug detecton: GCN Circular 34812) was also detected with three GRID detectors, GRID-03B, GRID-04, and GRID-07, onboard two different CubeSats.

The event was triggered by GRID on 2023-10-04 at 08:23:35.0 UTC. The measured burst duration (T90) in the 30-2000 keV range is approximately 6.1 +/- 1.0 seconds.

GRID is a student-led project to monitor the transient gamma-ray sky with multiple detectors onboard different nanosatellites in the era of multi-messenger astronomy. For more information about GRID, please refer to the following references: https://doi.org/10.1007/s10686-019-09636-w and https://doi.org/10.1007/s10686-021-09819-4.


GRB_name: GRB231020A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34869
SUBJECT: GRB 231020A: Fermi GBM Detection
DATE:    23/10/21 15:40:20 GMT
FROM:    sumanbala2210@gmail.com

S. Bala (USRA) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 18:56:58.30 UT on 20 October 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 231020A (trigger 719521023/231020790).

The Fermi GBM Final Real-time Localization is reported in GCN 34856.

The GBM light curve consists of a single bright peak with a duration (T90)
of about 9.3 s (50-300 keV). The time-averaged spectrum
from T0-0.5 to T0+21 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is -1.34 +/- 0.01 and the cutoff energy,
parameterized as Epeak, is 145 +/- 3 keV.

The event fluence (10-1000 keV) in this time interval is
(3.81 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+6.6 s in the 10-1000 keV band is 87.2 +/- 0.8 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB231024A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34876
SUBJECT: GRB 231024A: Fermi GBM Final Localization
DATE:    23/10/24 21:38:20 GMT
FROM:    Lorenzo Scotton at UAH <lscottongcn@outlook.com>

The Fermi GBM team reports the detection of a likely SHORT GRB

"At 13:20:34.42 UT on 24 October 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 231024A (trigger 719846439/231024556).

The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 15.4, Dec = -14.1 (J2000 degrees, equivalent to J2000 01h 01m, -14d 05'),
with a statistical uncertainty of 12.6 degrees.

The angle from the Fermi LAT boresight is 89.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231024556/quicklook/glg_skymap_all_bn231024556.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231024556/quicklook/glg_healpix_all_bn231024556.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231024556/quicklook/glg_lc_medres34_bn231024556.gif"


GRB_name: GRB231024A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34878
SUBJECT: GRB 231024A: GOTO optical counterpart candidate
DATE:    23/10/25 06:23:08 GMT
FROM:    Ben Gompertz at U of Birmingham <b.gompertz@bham.ac.uk>

B. P. Gompertz, K. Ackley, D. K. Galloway, T. Killestein, R. Starling, M. J. Dyer, J. Lyman, K. Ulaczyk, F. Jimenez-Ibarra, A. Kumar, D. O'Neill, D. Steeghs, V. Dhillon, P. O'Brien, G. Ramsay, K. Noysena, R. Kotak, R. P. Breton, L. K. Nuttall, E. Pall'e and D. Pollacco report on behalf of the GOTO collaboration:

We report on observations with the Gravitational-wave Optical Transient Observer (GOTO, Steeghs et al. 2022) in response to GRB 231024A (Fermi GBM Team, GCN 34876). Targeted observations were performed by GOTO-North between 22:15:31 UT on 2023-10-24 and 00:31:24 UT on 2023-10-25 (starting 0.37 days after trigger). Each observation consisted of 4x90s exposures in the GOTO L-band (400-700 nm).

Images were processed immediately after acquisition using the GOTO pipeline. Difference imaging was performed using recent survey observations of the same pointings. Source candidates were initially filtered using a classifier (Killestein et al. 2021) and cross-matched against a variety of contextual and minor planet catalogues. Human vetting was carried out in real time on any candidates that passed the above checks.

We identify one candidate optical counterpart within the GBM 90% localisation region that is not present prior to the GRB trigger time in previous GOTO observations, the ZTF observations provided by the Lasair broker (Smith et al. 2019), or the ATLAS forced photometry server (Shingles et al. 2021). The most recent observation of the field was taken by ATLAS at 05:05:19 UT on 2023-10-24, 8.25 hours before trigger.

Name | RA(J2000) | Dec(J2000) | Filter | Mag(AB)
GOTO23baj | 00:55:07.30 | -15:15:19.43 | L | 18.37 +/- 0.07

The source is consistent with a galaxy in the WISExSuperCOSMOS PhotoZ SVM catalogue (Bilicki et al., 2016) with a reported redshift of z = 0.0734 +/- 0.0354 and is consistent with a power-law decay with an index of t^-0.7 across 3 epochs of observations.

Magnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and are not corrected for Galactic extinction.

Observations are ongoing.

GOTO (https://goto-observatory.org) is a network of telescopes that is principally funded by the STFC and operated at the Roque de los Muchachos Observatory on La Palma, Spain, and Siding Spring Observatory in NSW, Australia, on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory & Planetarium, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT), the University of Turku, the University of Portsmouth, the University of Manchester and the Instituto de Astrofisica de Canarias (IAC).


GRB_name: GRB231020B
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34879
SUBJECT: GRB 231020B: AstroSat CZTI detection
DATE:    23/10/25 06:43:53 GMT
FROM:    Gaurav Waratkar at IIT Bombay <gauravwaratkar@iitb.ac.in>

P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a GRB 231020B which was also detected by Fermi - GBM (Fermi GBM Team, GCN Circ. 34862).

The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2023-10-20 21:35:57.50 UTC. The measured peak count rate associated with the burst is 148 (+30, -16) counts/s above the background in the combined data of two quadrants (out of four), with a total of 1242 (+296, -361) counts. The local mean background count rate was 177 (+1, -3) counts/s. Using cumulative rates, we measure a T90 of 34 (+8, -16) s. 

The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-10-20 21:35:55.27 UTC. The measured peak count rate associated with the burst is 274 (+74, -45) counts/s above the background in the combined data of all quadrants, with a total of 1637 (+667, -683) counts. The local mean background count rate was 1501 (+5, -6) counts/s. We measure a T90 of 25 (+11, -15) s from the cumulative Veto light curve.

CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.

CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB231020A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34880
SUBJECT: GRB 231020A: AstroSat CZTI detection
DATE:    23/10/25 08:23:10 GMT
FROM:    Gaurav Waratkar at IIT Bombay <gauravwaratkar@iitb.ac.in>

P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a GRB 231020A which was also detected by Fermi - GBM (Fermi GBM Team, GCN Circ. 34856).

The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2023-10-20 18:57:05.75 UTC. The measured peak count rate associated with the burst is 144 (+46, -21) counts/s above the background in the combined data of two quadrants (out of four), with a total of 454 (+118, -182) counts. The local mean background count rate was 187 (+2, -4) counts/s. Using cumulative rates, we measure a T90 of 8 (+3, -6) s.

The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-10-20 18:57:05.27 UTC. The measured peak count rate associated with the burst is 1728 (+90, -99) counts/s above the background in the combined data of all quadrants, with a total of 5763 (+584, -605) counts. The local mean background count rate was 1489 (+6, -6) counts/s. We measure a T90 of 11 (+8, -2) s from the cumulative Veto light curve.

CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.

CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB231024A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34881
SUBJECT: GRB 231024A: LCOGT and ZTF detections of the GOTO optical counterpart candidate
DATE:    23/10/25 14:05:57 GMT
FROM:    ipf@iac.es

A. Iglesias-LÃ³pez, H. Akoudad-Ekajouan, C. Araujo-Ãlvarez, C. Arrizabalaga-DÃ­az-Caneja, F. Barnes-SÃ¡nchez, P. Eguiguren-Arrizabalaga, G.A. Jaimes-Illanes, P. JimÃ©nez-SÃ¡nchez, S. Lamolda-Mir, A. Mang-RomÃ¡n, G. Marrero-Ramallo, P.P. Meni-Gallardo, I. Ruiz-Cejudo (ULL), M. SÃ¡nchez-AndÃºjar (ULL and IAC), V. Wienzek (ULL), E. Esparza-Borges, F. Tinaut-Ruano, and I. PÃ©rez-Fournon (IAC and ULL) report:

We report LCOGT and ZTF detections of GOTO23baj, the GOTO optical counterpart candidate of GRB 231024A.

The likely SHORT GRB 231024A has been reported by the Fermi GBM Team (GCN 34876). Gompertz et al. (GCN 34878) have reported a GOTO optical counterpart candidate, GOTO23baj (AT 2023vuc), at RA (J2000) = 00:55:07.30, Dec (J2000) = -15:15:19.43 and L = 18.37 +/- 0.07 on 2023-10-24 22:15:30.

We triggered Las Cumbres Observatory follow-up imaging and detected a source at the position of GOTO23baj on UT 2023-10-25 07:23:31 at SDSS r' = 18.28 +/- 0.12 in a single 300 sec exposure using one of the Las Cumbres Observatory 40 cm telescopes at Heleakala Observatory (Maui, Hawaii).

This transient has also been detected by ZTF (ZTF23abnevza) on UT 2023-10-25 07:42:27 at ZTF g = 18.193 Â± 0.082.

This work makes use of observations from the Las Cumbres Observatory global telescope network (program IAC2023B-001) and is based on observations made with the Las Cumbres Observatory's education network telescopes that were upgraded through generous support from the Gordon and Betty Moore Foundation. These observations are part of a course in Astrophysical Techniques of the Master in Astrophysics of the Astrophysics Department of the University of La Laguna and Instituto de Astrofisica de Canarias (Tenerife, Canary Islands, Spain).


GRB_name: GRB231024A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34882
SUBJECT: GRB 231024A: X-shooter spectroscopy of AT2023vuc/GOTO23baj reveals a young supernova with flash ionisation features
DATE:    23/10/25 14:50:13 GMT
FROM:    Daniele B. Malesani at IMAPP / Radboud University <d.malesani@astro.ru.nl>

A. Saccardi (GEPI/Paris Obs.), G. Leloudas (DTU Space), A. J. Levan (Radboud Univ. and Warwick Univ.), L. Izzo (INAF Napoli and DARK/NBI), A. de Ugarte Postigo (OCA), B. P. Gompertz (Birmingham), P. Jonker (Radboud Univ.), J. Palmerio (GEPI/Paris Obs.), E. Pian (INAF/OAS), G. Pugliese (Amsterdam), K. Wiersema (Univ. Herfordshire), R. A. M. J. Wijers (Amsterdam), report on behalf of a larger collaboration:

Following the discovery of GOTO23baj/AT2023vuc (Gompertz et al. 2023, GCN 34878; Iglesias-LÃ³pez et al., GCN 34881) within the error box of GRB 231024A (Fermi GBM Team, GCN 34876), we obtained a spectrum of the optical counterpart candidate with X-shooter. Observations started at 07:58 UT on 2023 Oct 25.

The spectrum is dominated by emission lines, that can be interpreted as strong He II 4686 (with a blue shoulder possibly associated with NIII / CIII) together with H-alpha and H-beta on top of a blue continuum, at a common redshift z = 0.056. The spectrum is consistent with those of very young supernovae that demonstrate flash-ionisation features a few hours to days after shock breakout (e.g. Gal-Yam et al. 2014, Nature, 509, 471). This is consistent with the non detection of the transient by ATLAS just 8 hours prior to the GOTO discovery. A comparison with SNID (Blondin & Tonry 2007, ApJ, 666, 1024) shows that the best matching template is that of SN 1998S at 12 days before maximum. Based on photometry reported by Iglesias-LÃ³pez et al. (GCN 34881), the transient absolute magnitude is around M_r = -18.8 (AB).

Considering the large GRB uncertainty region (12.6 deg radius) and its short duration, GOTO23baj/AT2023vuc is likely unrelated to GRB 231024A. However, this is a very young supernova and further observations are encouraged.

We acknowledge expert support from the ESO observing staff in Paranal, in particular Jonathan Smoker, Matias Jones and Felipe Gaete.


GRB_name: GRB231025A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34883
SUBJECT: GRB 231025A: Fermi GBM Final Localization
DATE:    23/10/25 15:38:43 GMT
FROM:    Joe Mangan at IJCLab <joseph.mangan@ijclab.in2p3.fr>

The Fermi GBM team reports the detection of a likely SHORT GRB

"At 06:46:59.59 UT on 25 October 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 231025A (trigger 719909224/231025283).

The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 190.96, Dec = -53.08 (J2000 degrees, equivalent to J2000 12h 44m, -53d 05'),
with a statistical uncertainty of 16.32 degrees.

The angle from the Fermi LAT boresight is 113 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231025283/quicklook/glg_skymap_all_bn231025283.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231025283/quicklook/glg_healpix_all_bn231025283.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231025283/quicklook/glg_lc_medres34_bn231025283.gif"


GRB_name: GRB231025A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34884
SUBJECT: GRB 231025A: Swift/BAT-GUANO detection of a likely short burst
DATE:    23/10/25 16:51:56 GMT
FROM:    Samuele Ronchini at PSU <sjs8171@psu.edu>

Samuele Ronchini (PSU), Aaron Tohuvavohu (U Toronto), James DeLaunay (PSU), Gayathri Raman (PSU), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC) report:

Swift/BAT did not localize GRB 231025A onboard (T0: 22023-10-25T06:46:59.59 UTC,Fermi GCN 34883). 

The Fermi notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). 

Upon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.

The BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), detects the burst with a sqrt(TS) of 10.1 in a 4.096 s analysis time bin, starting at T0 -4.0961 s.

NITRATES results are consistent with a burst detected inside the BAT coded FOV, with a DeltaLLHOut of 13.17, and are consistent with Fermi GBM's localization (GCN 34883).

See Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretation of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut.

GUANO is a fully autonomous, extremely low latency, spacecraft
commanding pipeline designed for targeted recovery of BAT event mode
data around the times of compelling astrophysical events to enable
more sensitive GRB searches.

A live reporting of Swift/BAT event data recovered by GUANO can be
found at: https://www.swift.psu.edu/guano/


GRB_name: GRB231024A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34885
SUBJECT: GRB 231024A: Fermi GBM Observation
DATE:    23/10/25 19:47:00 GMT
FROM:    Lorenzo Scotton at UAH <lscottongcn@outlook.com>

L. Scotton (UAH), O.J. Roberts (USRA/NASA-MSFC), C. Fletcher (USRA),
E. Burns (LSU) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 13:20:34.42 UT on 24 October 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 231024A (trigger 719846439/231024556). This trigger 
was later followed up by GOTO (Gompertz et al. 2023, GCN 34878), 
LCOGT and ZTF (Iglesias-LÃ³pez et al. 2023, GCN 34881), 
and X-shooter (Saccardi et al. 2023, GCN 34882) identifying 
a candidate afterglow (AT2023vuc/GOTO23baj) and suggested it was the counterpart.

The Fermi GBM Final Localization was reported in GCN 34876.

The angle from the Fermi LAT boresight is 89 degrees.

The GBM light curve consists of a single peak  
with a duration (T90) of about 0.05s. The time-averaged spectrum
from T0-0.064 to T0+0.064 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is -0.76 +/- 0.26 and the cutoff energy,
parameterized as Epeak, is 516 +/- 202 keV. 
A Band function fits the spectrum equally well with
Epeak = 519 +/- 203 keV, alpha = -0.75 +/- 0.26 and beta = -8.82 +/- 0.01.

The event fluence (10-1000 keV) in this time interval is
(2.9 +/- 0.4)E-07 erg/cm^2. The 64-msec peak photon flux measured
starting from T0-0.06 s in the 10-1000 keV band is 8 +/- 1 ph/s/cm^2.

Due to the large GBM localization error radius of 12.6 degrees, 
as reported in GCN 34876, we are currently unable to confirm or deny 
the association between GRB 231024A and AT2023vuc/GOTO23baj.
However, considered the spectroscopic classification of the optical transient 
as an early supernova we expect it to be unrelated to the gamma-ray trigger. 
The alignment in time and space is likely coincidental, in part due 
to the large localization region.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB231025A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34886
SUBJECT: GRB 231025A: Fermi GBM Observation
DATE:    23/10/25 21:04:53 GMT
FROM:    Joe Mangan at IJCLab <joseph.mangan@ijclab.in2p3.fr>

J.Mangan (CNRS/IJCLab) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 06:46:59.59 UT on 25 October 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 231025A (trigger 719909224/231025283).
which was also detected by Swift/BAT-GUANO (Ronchini et al. 2023, GCN 34884).
The Fermi GBM Final Real-time Localization is reported in GCN 34883.

The GBM light curve consists of a single emission episode with a duration (T90)
of about 6 s (50-300 keV). The time-averaged spectrum
from T0-2.0 to T0+4.1 s is best fit by a simple power law function with index -1.4 +/- 0.1.

The event fluence (10-1000 keV) in this time interval is
(1.2 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-3.1 s in the 10-1000 keV band is 1.3 +/- 0.3 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB231019A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34888
SUBJECT: GRB 231019A: Glowbug gamma-ray detection
DATE:    23/10/26 20:57:26 GMT
FROM:    C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>

C.C. Cheung, M. Kerr, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:
 
The Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 231019A, which was also detected by Fermi/GBM, INTEGRAL/SPI-ACS, and VZLUSAT-2 (GCN 34842, 34866).
 
Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-10-19 17:09:56.896 with a duration of 2.1 s and a total significance of about 12.3 sigma.  The light curve comprises a single peak.
 
Using a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=4.3 and a cutoff energy ("Epeak") of 130 keV.  The modeled 10-10000 keV fluence is 2.4e-07 erg/cm^2.
 
The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.
 
Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC.  It was launched on 2023 March 15 aboard the Department of Defense Space Test Programâ€™s STP-H9 to the ISS.  The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.
 
[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006
 
Distribution Statement A: Approved for public release.  Distribution is unlimited.


GRB_name: GRB231028A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34893
SUBJECT: GRB 231028A: Fermi GBM Final Real-time Localization
DATE:    23/10/28 04:19:34 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 04:09:06 UT on 28 Oct 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231028A (trigger 720158951.657448 / 231028173).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 214.3, Dec = 21.8 (J2000 degrees, equivalent to J2000 14h 17m, 21d 48'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 23.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231028173/quicklook/glg_skymap_all_bn231028173.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231028173/quicklook/glg_healpix_all_bn231028173.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231028173/quicklook/glg_lc_medres34_bn231028173.gif


GRB_name: GRB231028A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34894
SUBJECT: GRB 231028A: Swift detection of a burst
DATE:    23/10/28 04:28:17 GMT
FROM:    David Palmer at LANL <palmer@lanl.gov>


M. A. Williams (PSU), S. Dichiara (PSU), D. M. Palmer (LANL),
T. Sakamoto (AGU) and B. Sbarufatti (INAF-OAB) report on behalf of the
Neil Gehrels Swift Observatory Team:

At 04:09:09 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 231028A (trigger=1193078).  Swift did not slew to the 
GRB location due to an observing constraint. 
The BAT on-board calculated location is 
RA, Dec 214.029, +20.895 which is 
   RA(J2000) = 14h 16m 07s
   Dec(J2000) = +20d 53' 42"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex peak
structure with a duration of at least 18 sec, although the immediately
available data is truncated at T+8s due to packet loss. The peak count
rate was ~8500 counts/sec (15-350 keV), at ~1 sec after the trigger. 

Due to a Sun observing constraint, Swift cannot slew to the BAT
position until 15:45 UT on 2023 November 22. There will thus be no XRT
or UVOT data for this trigger before this time. 

Swift Triggers have recently been re-enabled while we are dealing
with attitude problems that can lead to star tracker Loss-of-Lock (LoL). 
We are confident that this GRB was not caused by an LoL event because:
1) The Swift_BAT_Position notice did not indicate a LoL. 
  (See the comments section.)
2) This burst location was not near to a known bright source. 
3) There was a simultaneous trigger by Fermi-GBM. 
4) This is a rate-triggered burst on a 1.024 s timescale, while most LoL
false triggers have been 'Image Triggers' with duration 64 s and longer. 

Observers should continue to be cautious (especially checking the
comments for LoL) in future GCN notices going forward. 

Burst Advocate for this burst is M. A. Williams (mjw6837 AT psu.edu). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB231028A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34897
SUBJECT: Swift GRB 231028A: Global MASTER-Net observations report
DATE:    23/10/28 22:40:30 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-Kislovodsk robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the Swift GRB 231028A ( M. A. Williams et al., GCN 34894) errorbox  39827 sec after notice time and 39846 sec after trigger time at 2023-10-28 15:13:16 UT, with upper limit up to  14.5 mag. Observations started at twilight.  The observations began at zenith distance = 78 deg. The sun  altitude  is -12.3 deg. 

MASTER-Tunka robotic telescope  located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the Swift GRB 231028A errorbox  65649 sec after notice time and 65669 sec after trigger time at 2023-10-28 22:23:38 UT, with upper limit up to  16.0 mag. Observations started at twilight.  The observations began at zenith distance = 79 deg. The sun  altitude  is -14.4 deg. 

The galactic latitude b = 69 deg., longitude l = 20 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2291906

We obtain a following upper limits.  

Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

   39937 |   MASTER-Kislovodsk |   C |   180 | 13.6 |        
   40139 |   MASTER-Kislovodsk |   C |   180 | 13.0 |        
   40340 |   MASTER-Kislovodsk |   C |   180 | 14.5 |        
   41732 |   MASTER-Kislovodsk |   C |   180 | 13.0 |        
   65699 |        MASTER-Tunka |   C |    60 | 16.0 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB231028A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34899
SUBJECT: GRB 231028A: Fermi GBM Detection
DATE:    23/10/28 22:45:43 GMT
FROM:    Peter Veres at University of Alabama in Huntsville <veresp@gmail.com>

P. Veres (UAH) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 04:09:06.66 UT on 28 October 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 231028A (trigger 720158951/231028173),
which was also detected by the Swift/BAT (Williams et al. 2023, GCN 34894).
The Fermi GBM Final Real-time Localization (GCN 34893) is consistent with the Swift position.


The GBM light curve consists of multiple peaks with a duration (T90)
of about 34.8 s (50-300 keV). The time-averaged spectrum
from T0-4.1 to T0+43.0 s is best fit by
a Band function with Epeak = 157 +/- 11 keV,
alpha = -0.72 +/- 0.06, and beta = -2.13 +/- 0.08.

The event fluence (10-1000 keV) in this time interval is
(1.95 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+4.0 s in the 10-1000 keV band is 14.8 +/- 0.4 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB231028A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34900
SUBJECT: GRB 231028A:  Glowbug gamma-ray detection
DATE:    23/10/29 03:45:23 GMT
FROM:    J. Eric Grove at U.S. Naval Research Laboratory <eric.grove@nrl.navy.mil>

M. Kerr, C.C. Cheung, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:

The Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 231028A, which was also detected by Fermi/GBM (GCN 34893, 34899) and Swift/BAT (GCN 34894).
 
Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-10-28 04:09:01.344 with a duration of 47.1 s and a total significance of about 91.2 sigma.  The light curve comprises a structured main peak with at least two following peaks.
 
Using a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=1.9 and a cutoff energy ("Epeak") of 198 keV.  The modeled 10-10000 keV fluence is 9.8e-06 erg/cm^2.
 
The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.
 
Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC.  It was launched on 2023 March 15 aboard the Department of Defense Space Test Programâ€™s STP-H9 to the ISS.  The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.
 
[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006
 
Distribution Statement A: Approved for public release.  Distribution is unlimited.


GRB_name: GRB231028A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34901
SUBJECT: GRB 231028A: AstroSat CZTI detection
DATE:    23/10/29 03:47:02 GMT
FROM:    Gaurav Waratkar at IIT Bombay <gauravwaratkar@iitb.ac.in>

P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long GRB 231028A which was also detected by Fermi-GBM (Fermi GBM Team, GCN Circ. 34893, Veres et al., GCN Circ. 34899), Swift-BAT (Williams et al., GCN Circ. 34894), and  Glowbug (Kerr et al., GCN Circ. 34900).

The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2023-10-28 04:09:14.25 UTC. The measured peak count rate associated with the burst is 66 (+42, -4) counts/s above the background in the combined data of two quadrants (out of four), with a total of 273 (+88, -85) counts. The local mean background count rate was 156 (+1, -4) counts/s. Using cumulative rates, we measure a T90 of 7.8 (+0.9, -3.0) s. We caution that there was a 0.3 s readout dead time in CZTI after the detection of the burst. Hence, the T90 can be as large as 8.7 s for this GRB, with a lower limit of 4.8 s as estimated above by cumulative rates.

The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-10-28 04:09:13.77 UTC. The measured peak count rate associated with the burst is 605 (+74, -72) counts/s above the background in the combined data of all quadrants, with a total of 2924 (+529, -560) counts. The local mean background count rate was 1508 (+6, -7) counts/s. We measure a T90 of 6.2 (+2.3, -1.3) s from the cumulative Veto light curve.

CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.

CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB231020A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34903
SUBJECT: GRID detection of GRB 231020A
DATE:    23/10/29 11:39:09 GMT
FROM:    GRID Student Team at Tsinghua University <grid@tsinghua.edu.cn>

Chenyu Wang and Zirui Yang report on behalf of the GRID Collaboration:

The long-duration GRB 231020A (Fermi/GBM detection: GCN Circular 34856, AstroSat CZTI detection: GCN Circular 34880) was also detected with GRID-04.

The event was triggered by GRID on 2023-10-20 at 18:56:58 UTC. The measured burst duration (T90) in the 30-2000 keV range is approximately 9.8 +/- 2.0 s seconds.

GRID is a student-led project to monitor the transient gamma-ray sky with multiple detectors onboard different nanosatellites in the era of multi-messenger astronomy. For more information about GRID, please refer to the following references: https://doi.org/10.1007/s10686-019-09636-w and https://doi.org/10.1007/s10686-021-09819-4.


GRB_name: GRB231030A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34907
SUBJECT: GRB 231030A: Fermi GBM Final Real-time Localization
DATE:    23/10/30 00:18:11 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 00:07:34 UT on 30 Oct 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231030A (trigger 720317259.119418 / 231030005).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 46.8, Dec = 49.1 (J2000 degrees, equivalent to J2000 03h 07m, 49d 06'), with a statistical uncertainty of 16.3 degrees.

The angle from the Fermi LAT boresight is 71.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231030005/quicklook/glg_skymap_all_bn231030005.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231030005/quicklook/glg_healpix_all_bn231030005.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231030005/quicklook/glg_lc_medres34_bn231030005.gif


GRB_name: GRB231030A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34908
SUBJECT: Fermi GRB 231030A: Global MASTER-Net observations report
DATE:    23/10/30 00:46:38 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-Tavrida robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB 231030A ( Fermi GBM team, GCN 34907) errorbox  385 sec after notice time and 423 sec after trigger time at 2023-10-30 00:14:37 UT, with upper limit up to  17.8 mag. The observations began at zenith distance = 26 deg. The sun  altitude  is -43.0 deg. 

The galactic latitude b = -8 deg., longitude l = 145 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2293042

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

     454 | 2023-10-30 00:14:37 |      MASTER-Tavrida | (03h 04m 47.73s , +31d 27m 09.4s) |   C |    60 | 16.6 |        
    1375 | 2023-10-30 00:29:59 |      MASTER-Tavrida | (04h 11m 37.15s , +39d 06m 30.5s) |   C |    60 | 17.8 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB231028A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34909
SUBJECT: GRB 231028A: CALET Gamma-Ray Burst Monitor detection
DATE:    23/10/30 04:07:26 GMT
FROM:    Yuta Kawakubo at Louisiana State University <kawakubo1@lsu.edu>

A. Yoshida, T. Sakamoto, S. Sugita (AGU), Y. Kawakubo (LSU),
K. Yamaoka (Nagoya U), S. Nakahira (JAXA),
Y. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (Waseda U),
Y. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC),
M. L. Cherry (LSU), S. Ricciarini (U of Florence),
P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long GRB 231028A (Fermi GBM Final Real-time Localization: 
Fermi GBM team, GCN Circ. 34893; Swift detection: Williams et al.,
GCN Circ. 34894; Fermi GBM Detection: Veres et al., GCN Circ. 34899; 
Glowbug gamma-ray detection: Kerr et al., GCN Circ. 34900; 
AstroSat CZTI detection: Navaneeth et al.,  GCN Circ. 34901) 
triggered the CALET Gamma-ray Burst Monitor (CGBM) at 04:09:04.43
UTC on 28 October 2023
(http://cgbm.calet.jp/cgbm_trigger/flight/1382501309/index.html).
The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure that starts
at T+0.25 sec, peaks at T+6.5 sec, and ends at T+47.5 sec.
The T90 and T50 durations measured by the SGM data are 36.1 +/- 1.2 sec
and 6.9 +/- 1.1 sec (40-1000 keV), respectively.

The ground-processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1382501309/

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at Waseda University.


GRB_name: GRB231024A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34910
SUBJECT: GRB 231024A: AKO Optical Counterpart Candidate
DATE:    23/10/30 12:04:57 GMT
FROM:    Mohammad Odeh at Al Khatim Observatory M44 <mshodeh@gmail.com>

Mohammad Odeh (Al-Khatim Observatory, AKO, operated by the International
Astronomical Center in Abu Dhabi, UAE), and Dalya Akl, Ilmah Abdi, and
Nidhal Guessoum (American University of Sharjah, UAE), report:

We observed the field of GRB 231024A (Fermi GBM Team, GCN 34876; Gompertz
et al., GCN 34878; Iglesias-LÃ³pez et al., GCN 34881; Saccardi et al., GCN
34882; Scotton et. al., GCN 34885) with our 0.36m f/7.7 robotic telescope.

The observation was done on 29 October 2023 from 17:31 UT to 19:14 UT, 5.21
days after the trigger. We obtained 32x180 sec. images using (Ic) filter.

We detected the optical afterglow candidate of GRB 231024A in our stacked
images at the coordinates (J2000): R.A.: 00:55:07.28, Dec.: -15:15:19.6,
which is consistent with the observation of (Gompertz et al., GCN 34878).

The following magnitude was calculated using the Atlas catalogue as a
reference:
-----------------------------------------------------------------------------
ObsTime (mid), Exposure (sec), Filter, Mag, MagRMS
-----------------------------------------------------------------------------
2023-10-29T18:24:01Z, 32x180s (stacked), Ic, 18.3, 0.16
-----------------------------------------------------------------------------

The magnitude is not corrected for galactic extinction.


GRB_name: GRB231028A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34914
SUBJECT: GRB 231028A: Swift-BAT refined analysis
DATE:    23/10/30 17:03:43 GMT
FROM:    Tyler Parsotan  at NASA GSFC <tyler.parsotan@nasa.gov>

H. A. Krimm (NSF), S. D. Barthelmy (GSFC),
S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa),
C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),
M. Stamatikos (OSU) (i.e. the Swift-BAT team):

Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 231028A (trigger #1193078)
(Williams et al., GCN Circ. 34894).  The BAT ground-calculated position is
RA, Dec = 214.016, 20.897 deg which is
   RA(J2000)  =  14h 16m 03.8s
   Dec(J2000) = +20d 53' 47.8"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 68%.

The mask-weighted lightcurve shows a broad initial pulse with subsequent
extended emission.
T90 (15-350 keV) is 37.23 +- 0.98 sec (estimated error including systematics).

The time-averaged spectrum from T-6.86 to T+41.95 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.40 +- 0.04.  The fluence in the 15-150 keV band is 7.2 +- 0.2 x 10^-06 erg/cm2.
The 1-sec peak photon flux measured from T+1.06 sec in the 15-150 keV band
is 8.6 +- 0.4 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/1193078/BA/


GRB_name: GRB231030B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34915
SUBJECT: GRB 231030B: Fermi GBM Final Real-time Localization
DATE:    23/10/30 20:08:47 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 19:58:19 UT on 30 Oct 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231030B (trigger 720388704.937126 / 231030832).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 244.0, Dec = 56.5 (J2000 degrees, equivalent to J2000 16h 15m, 56d 30'), with a statistical uncertainty of 1.1 degrees.

The angle from the Fermi LAT boresight is 47.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231030832/quicklook/glg_skymap_all_bn231030832.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231030832/quicklook/glg_healpix_all_bn231030832.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231030832/quicklook/glg_lc_medres34_bn231030832.gif


GRB_name: GRB231030B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34916
SUBJECT: GRB 231030B: BALROG localization (Fermi Trigger 720388704 / GRB 231030832)
DATE:    23/10/30 20:28:59 GMT
FROM:    Jochen Greiner at MPE <jcgrog@mpe.mpg.de>

T. Preis, B. Biltzinger, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
720388704 at 19:58:19 on 30 Oct. 2023 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 249.1+/-2.4 deg
Decl.(2000.0) = 63.3+/-0.9 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB231030832/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB231030832/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB231030832/json

                        


GRB_name: GRB231020A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34917
SUBJECT: IPN triangulation of GRB 231020A
DATE:    23/10/30 20:36:49 GMT
FROM:    Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>

A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin
on behalf of the MGNS/BepiColombo and HEND/Mars Odyssey teams,

J. Benkhoff on behalf of the BepiColombo team,

D. Svinkin, D. Frederiks, A. Ridnaia, A. Lysenko,
and T. Cline on behalf of the Konus-Wind team,

A. Goldstein, M. S. Briggs, C. Wilson-Hodge,
and E. Burns on behalf of the Fermi GBM team,

E. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,

S. Barthelmy, J. Cummings, H. Krimm, D. Palmer, and A. Tohuvavohu
on behalf of the Swift-BAT team,

and

W. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,
and A.S. Gardner on on behalf of the GRS-Odyssey GRB team,
report:

The long-duration GRB 231020A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 34856;
Bala et al., GCN Circ. 34869;
BALROG localization: Preis et al., GCN Circ. 34861;
AstroSat-CZTI detection: Navaneeth et al., GCN Circ. 34880;
GRID detection: Wang and Yang, GCN Circ. 34903)
was detected by Fermi (GBM trigger 719521023), INTEGRAL (SPI-ACS),
Konus-Wind, Swift (BAT), Mars-Odyssey (HEND), BepiColombo (MGNS),
AstroSat (CZTI), and GRID, at about 68218 s UT (18:56:58).
The burst was outside the coded field of view of the BAT.

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
 ---------------------------------------------
  RA(2000), deg                 Dec(2000), deg
 ---------------------------------------------
 Center:
  314.493 (20h 57m 58s) -29.254 (-29d 15' 15")
 Corners:
  314.061 (20h 56m 15s) -28.067 (-28d 04' 02")
  314.696 (20h 58m 47s) -29.893 (-29d 53' 33")
  314.881 (20h 59m 31s) -30.286 (-30d 17' 09")
  314.275 (20h 57m 06s) -28.562 (-28d 33' 43")
 ---------------------------------------------
The error box area is 247 sq. arcmin, and its maximum
dimension is 2.3 deg (the minimum one is 2.2 arcmin).
The Sun distance was 101 deg.

This localization may be improved.

The IPN localization is consistent with, but reduces the area of,
the Fermi-GBM final localization.

A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB231020_T68224/IPN

The Konus-Wind time history and spectrum will be given
in a forthcoming GCN Circular.


GRB_name: GRB231030B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34918
SUBJECT: Fermi GRB 231030B: Global MASTER-Net observations report
DATE:    23/10/30 20:46:00 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-Tunka robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB 231030B ( Fermi GBM team, GCN 34915) errorbox 118 sec after trigger time at 2023-10-30 20:00:18 UT, with upper limit up to  15.5 mag. The observations began at zenith distance = 70 deg. The sun  altitude  is -36.7 deg. 

MASTER-Tavrida robotic telescope  located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB 231030B errorbox  53 sec after notice time and 175 sec after trigger time at 2023-10-30 20:01:15 UT, with upper limit up to  18.2 mag. The observations began at zenith distance = 71 deg. The sun  altitude  is -54.7 deg. 

MASTER-Kislovodsk robotic telescope  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB 231030B errorbox  446 sec after notice time and 567 sec after trigger time at 2023-10-30 20:07:47 UT, with upper limit up to  15.8 mag. The observations began at zenith distance = 74 deg. The sun  altitude  is -59.1 deg. 

The galactic latitude b = 43 deg., longitude l = 86 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2293463

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

     121 | 2023-10-30 20:00:18 |        MASTER-Tunka | (16h 13m 30.71s , +58d 06m 31.2s) |   C |     5 | 14.4 |        
     155 | 2023-10-30 20:00:49 |        MASTER-Tunka | (16h 13m 43.99s , +53d 32m 52.4s) |   C |    10 | 15.1 |        
     195 | 2023-10-30 20:01:15 |      MASTER-Tavrida | (16h 20m 18.41s , +56d 18m 19.3s) |   C |    40 | 17.5 |        
     194 | 2023-10-30 20:01:18 |        MASTER-Tunka | (16h 13m 44.06s , +53d 32m 52.5s) |   C |    30 | 15.5 |        
     243 | 2023-10-30 20:02:02 |      MASTER-Tavrida | (16h 20m 24.49s , +56d 17m 16.7s) |   C |    40 | 17.5 |        
     238 | 2023-10-30 20:02:08 |        MASTER-Tunka | (16h 13m 44.28s , +53d 32m 52.5s) |   C |    20 | 15.5 |        
     278 | 2023-10-30 20:02:47 |        MASTER-Tunka | (16h 13m 44.42s , +53d 32m 52.6s) |   C |    20 | 15.3 |        
     296 | 2023-10-30 20:02:51 |      MASTER-Tavrida | (16h 20m 19.47s , +56d 16m 14.4s) |   C |    50 | 18.0 |        
     315 | 2023-10-30 20:03:26 |        MASTER-Tunka | (16h 13m 44.60s , +53d 32m 52.8s) |   C |    15 | 15.1 |        
     363 | 2023-10-30 20:03:48 |      MASTER-Tavrida | (16h 20m 25.51s , +56d 16m 32.7s) |   C |    70 | 18.0 |        
     349 | 2023-10-30 20:04:01 |        MASTER-Tunka | (16h 13m 44.71s , +53d 32m 52.6s) |   C |    15 | 15.2 |        
     383 | 2023-10-30 20:04:35 |        MASTER-Tunka | (16h 13m 44.83s , +53d 32m 52.9s) |   C |    15 | 15.2 |        
     446 | 2023-10-30 20:05:05 |      MASTER-Tavrida | (16h 20m 22.32s , +56d 17m 57.1s) |   C |    80 | 17.9 |        
     423 | 2023-10-30 20:05:09 |        MASTER-Tunka | (16h 13m 45.01s , +53d 32m 54.2s) |   C |    25 | 15.3 |        
     464 | 2023-10-30 20:05:53 |        MASTER-Tunka | (16h 13m 45.18s , +53d 32m 55.1s) |   C |    20 | 15.4 |        
     503 | 2023-10-30 20:06:32 |        MASTER-Tunka | (16h 13m 45.35s , +53d 32m 55.4s) |   C |    20 | 15.3 |        
     543 | 2023-10-30 20:06:32 |      MASTER-Tavrida | (16h 20m 22.35s , +56d 16m 18.7s) |   C |   100 | 17.9 |        
     540 | 2023-10-30 20:07:11 |        MASTER-Tunka | (16h 13m 45.45s , +53d 32m 55.2s) |   C |    15 | 15.2 |        
     623 | 2023-10-30 20:07:47 |   MASTER-Kislovodsk | (16h 16m 11.19s , +56d 43m 03.7s) |  P| |   110 | 14.3 |        
     660 | 2023-10-30 20:08:20 |      MASTER-Tavrida | (16h 20m 25.77s , +56d 18m 01.2s) |   C |   120 | 18.0 |        
     616 | 2023-10-30 20:08:25 |        MASTER-Tunka | (16h 13m 45.71s , +53d 32m 56.8s) |   C |    20 | 15.3 |        
     768 | 2023-10-30 20:09:57 |   MASTER-Kislovodsk | (16h 16m 15.48s , +56d 44m 31.6s) |  P| |   140 | 14.3 |        
     802 | 2023-10-30 20:10:27 |      MASTER-Tavrida | (16h 20m 19.55s , +56d 17m 03.2s) |   C |   150 | 18.0 |        
     943 | 2023-10-30 20:12:38 |   MASTER-Kislovodsk | (16h 16m 08.40s , +56d 43m 33.6s) |  P| |   170 | 15.8 |        
     974 | 2023-10-30 20:13:04 |      MASTER-Tavrida | (16h 20m 21.18s , +56d 18m 01.6s) |   C |   180 | 18.0 |        
    1162 | 2023-10-30 20:16:11 |      MASTER-Tavrida | (16h 20m 27.23s , +56d 17m 00.1s) |   C |   180 | 18.1 |        
    1349 | 2023-10-30 20:19:19 |      MASTER-Tavrida | (16h 20m 21.81s , +56d 15m 59.2s) |   C |   180 | 18.1 |        
    1538 | 2023-10-30 20:22:28 |      MASTER-Tavrida | (16h 20m 27.02s , +56d 16m 26.7s) |   C |   180 | 18.1 |        
    1727 | 2023-10-30 20:25:36 |      MASTER-Tavrida | (16h 20m 25.49s , +56d 17m 39.9s) |   C |   180 | 18.2 |        
    1750 | 2023-10-30 20:25:59 |   MASTER-Kislovodsk | (16h 16m 17.38s , +56d 42m 28.2s) |  P| |   180 | 12.1 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB231030B
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34919
SUBJECT: GRB 231030B: AstroSat CZTI detection
DATE:    23/10/31 14:01:12 GMT
FROM:    Gaurav Waratkar at IIT Bombay <gauravwaratkar@iitb.ac.in>

P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a likely long GRB 231030B which was also detected by Fermi-GBM (Fermi GBM Team, GCN Circ. 34915).

The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2023-10-30 19:58:21.25 UTC. The measured peak count rate associated with the burst is 356 (+57, -41) counts/s above the background in the combined data of three quadrants (out of four), with a total of 1131 (+128, -178) counts. The local mean background count rate was 242 (+2, -4) counts/s. Using cumulative rates, we measure a T90 of 6.4 (+2.1, -2.3) s. 

The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-10-30 19:58:20.73 UTC. The measured peak count rate associated with the burst is 705 (+74, -78) counts/s above the background in the combined data of all quadrants, with a total of 2538 (+365, -401) counts. The local mean background count rate was 1484 (+6, -7) counts/s. We measure a T90 of 7.4 (+3.6, -3.1) s from the cumulative Veto light curve.

CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.

CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB231030B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34920
SUBJECT: GRB 231030B: Fermi GBM Detection
DATE:    23/10/31 14:33:19 GMT
FROM:    sumanbala2210@gmail.com

S. Bala (USRA) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 19:58:19.94 UT on 30 October 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 231030B (trigger 720388704/231030832).

The Fermi GBM Final Real-time Localization is reported in GCN 34915.

The GBM light curve consists of a single bright peak with a duration (T90)
of about 10.8 s (50-300 keV). The time-averaged spectrum
from T0+0.003 to T0+20.544 s is best fit by
a Band function with Epeak = 240 +/- 20 keV,
alpha = -0.78 +/- 0.04, and beta = -2.02 +/- 0.08.

The event fluence (10-1000 keV) in this time interval is
(2.17 +/- 0.05)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.3 s in the 10-1000 keV band is 24.7 +/- 0.4 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB231028B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34922
SUBJECT: GRB 231028B: VZLUSAT-2 detection
DATE:    23/10/31 19:20:48 GMT
FROM:    Marianna DafÄÃ­kovÃ¡ at Masaryk University <500025@mail.muni.cz>

M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory),  N. Werner  (Masaryk U.), M. Ohno (Hiroshima U.),  L. Meszaros, B. Csak (Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory),  T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU)  -- the VZLUSAT-2/GRB payload collaboration.

The long duration GRB 231028B (Fermi/GBM detection: trigger no. 720224759; Konus/WIND detection at 2023-10-28 22:25:55.024 UT) was detected by the GRB detectors on board of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).

The data acquisition was performed by the GRB detector units no. 0 and no. 1. The detection was confirmed at the peak time 2023-10-28 22:25:58 (22:26:31) UTC. The T90 duration is 43 s (37 s) and the significance during T90 reaches 13 sigma (8 sigma) for detector unit no. 0 (no. 1).

The light curve obtained by VZLUSAT-2 is available here:
https://vzlusat2.konkoly.hu/static/share/GRB231028B_GCN_VZLUSAT2.pdf

All VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/
The GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral.


GRB_name: GRB231030B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34923
SUBJECT: GRB 231030B: GRBAlpha detection
DATE:    23/10/31 19:40:44 GMT
FROM:    Marianna DafÄÃ­kovÃ¡ at Masaryk University <500025@mail.muni.cz>

M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal,  A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), yyT. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory),  T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.

The long-duration GRB 231030B (Fermi/GBM detection: GCN 34915; AstroSat/CZT detection: GCN 34919; INTEGRAL/SPI-ACS peak detection at 2023-10-30 ~19:58:20 UT) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023, A&A, 677, 40; arXiv:2302.10048).
The detection was confirmed at the peak time 2023-10-30 19:58:21 UTC. The T90 duration measured by GRBAlpha is 21 s and the overall significance during T90 reaches 15 sigma.

The light curve obtained by GRBAlpha is available here: 
https://grbalpha.konkoly.hu/static/share/GRB231030B_GCN.pdf

All GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ 
GRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume. 


GRB_name: GRB231101A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34924
SUBJECT: GRB 231101A: Fermi GBM Final Real-time Localization
DATE:    23/11/01 02:33:51 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 02:23:16 UT on 1 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231101A (trigger 720498201.799648 / 231101099).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 137.1, Dec = 13.3 (J2000 degrees, equivalent to J2000 09h 08m, 13d 18'), with a statistical uncertainty of 13.2 degrees.

The angle from the Fermi LAT boresight is 86.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231101099/quicklook/glg_skymap_all_bn231101099.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231101099/quicklook/glg_healpix_all_bn231101099.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231101099/quicklook/glg_lc_medres34_bn231101099.gif


GRB_name: GRB231101A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34929
SUBJECT: GRB 231101A: Glowbug gamma-ray detection
DATE:    23/11/02 15:13:39 GMT
FROM:    C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>

C.C. Cheung, M. Kerr, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:
 
The Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 231101A, which was also detected by Fermi/GBM (GCN 34924).
 
Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-11-01 02:23:14.776 with a duration of about 4 s and a total significance of about 6.4 sigma.  The light curve comprises a single peak.
 
Using a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=-0.8 and a cutoff energy ("Epeak") of 1023 keV.  The modeled 10-10000 keV fluence is 4.1e-07 erg/cm^2.
 
The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.
 
Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC.  It was launched on 2023 March 15 aboard the Department of Defense Space Test Programâ€™s STP-H9 to the ISS.  The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.
 
[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006
 
Distribution Statement A: Approved for public release.  Distribution is unlimited.


GRB_name: GRB231103A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34934
SUBJECT: GRB 231103A: Fermi GBM Final Real-time Localization
DATE:    23/11/03 14:52:04 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 14:41:30 UT on 3 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231103A (trigger 720715295.24961 / 231103612).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 14.0, Dec = -55.3 (J2000 degrees, equivalent to J2000 00h 56m, -55d 17'), with a statistical uncertainty of 5.2 degrees.

The angle from the Fermi LAT boresight is 53.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231103612/quicklook/glg_skymap_all_bn231103612.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231103612/quicklook/glg_healpix_all_bn231103612.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231103612/quicklook/glg_lc_medres34_bn231103612.gif


GRB_name: GRB231104A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34937
SUBJECT: GRB 231104A: Fermi GBM Final Real-time Localization
DATE:    23/11/04 01:57:53 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 01:47:28 UT on 4 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231104A (trigger 720755253.13875 / 231104075).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 8.0, Dec = 82.1 (J2000 degrees, equivalent to J2000 00h 32m, 82d 05'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 32.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231104075/quicklook/glg_skymap_all_bn231104075.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231104075/quicklook/glg_healpix_all_bn231104075.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231104075/quicklook/glg_lc_medres34_bn231104075.gif


GRB_name: GRB231104A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34938
SUBJECT: GRB 231104A: Swift detection of a bright burst
DATE:    23/11/04 02:34:58 GMT
FROM:    David Palmer at LANL <palmer@lanl.gov>


K. L. Page (U Leicester), J.D. Gropp (PSU), D. M. Palmer (LANL) and
M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 01:47:39 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 231104A (trigger=1194500).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 23.789, +83.791 which is 
   RA(J2000) = 01h 35m 09s
   Dec(J2000) = +83d 47' 27"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The available BAT light curve (up to T+8s)
showed a complex structure with a duration of at least 12 sec. 
The peak count rate was ~50,000 counts/sec (15-350 keV), 
at ~0 sec after the trigger. 

The XRT began observing the field at 01:49:10 UT, 90.2 seconds after
the BAT trigger. Using promptly downlinked data we find an
uncatalogued X-ray source with an enhanced position: RA, Dec 23.8113,
83.7912 which is equivalent to:
   RA(J2000)  = 01h 35m 14.7s
   Dec(J2000) = +83d 47' 28"
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This
location is 9 arcseconds from the BAT onboard position. This position
may be improved as more data are received; the latest position is
available at https://www.swift.ac.uk/sper. 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 860 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 25% of
the BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
BAT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.157. 

Burst Advocate for this burst is K. L. Page (klp5 AT leicester.ac.uk). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB231104A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34939
SUBJECT: GRB231104A: LCOGT Optical Upper Limits
DATE:    23/11/04 04:09:15 GMT
FROM:    Robert Strausbaugh at Eastern Illinois University <rstrausbaugh@eiu.edu>

R. Strausbaugh (Eastern Illinois University), A. Cucchiara (NASA) report on behalf of a larger collaboration:

We observed the Fermi GRB 231104A field (Fermi GBM team, GCN 34937) with the LCOGT 1-meter Sinistro instrument at the McDonald Observatory, USA site, on November 4, from 02:53 to 03:25 UT (corresponding to 1.10 to 1.63 hours from the GRB trigger time) with the SDSS r and i filters.

We performed a series of 3x300s exposures in each band.  We do not detect a source within the Swift-XRT error region around the candidate X-ray source (Page et al., GCN 34938) in either band.

The following 5-sigma upper limits are calculated using the PanSTARRS catalog as reference:

r > 22.6
i > 21.8

These magnitudes are not corrected for galactic extinction.


GRB_name: GRB231104A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34940
SUBJECT: GRB 231104A: Enhanced Swift-XRT position
DATE:    23/11/04 08:03:51 GMT
FROM:    Phil Evans at U of Leicester <pae9@star.le.ac.uk>

M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1654 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 231104A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 23.80633, +83.79348 which is equivalent
to:

RA (J2000): 01h 35m 13.52s
Dec (J2000): +83d 47' 36.5"

with an uncertainty of 2.2 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB231104A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34941
SUBJECT: GRB 231104A: Swift/UVOT Upper Limits
DATE:    23/11/04 12:44:11 GMT
FROM:    Paul Kuin at MSSL <npkuin@gmail.com>

N. P. M. Kuin (UCL/MSSL) and K. L. Page (U. Leicester) report on behalf
of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 231104A
91 s after the BAT trigger (Page et al., GCN Circ. 34940).  No optical
afterglow consistent with the XRT position (Goad et al., GCN Circ. 34940)
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC            91          241          147         >21.7
u_FC               304          553          246         >20.7
white               91         1709          411         >21.8
v                  633         1758          117         >19.3
b                  559         1684          117         >20.4
u                  304         1659          343         >20.9
w1                 683         1808          117         >19.7
m2                 659          679           20         >18.6

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.156 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB231104A
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34943
SUBJECT: GRB 231104A: Fermi-LAT detection
DATE:    23/11/04 16:29:52 GMT
FROM:    N. Di Lalla at Stanford University <niccolo.dilalla@stanford.edu>

G. Principe (University of Trieste), F. Longo (University of Trieste), N. Di Lalla (Stanford University), D. Tak (Seoul National University) report on behalf of the Fermi-LAT Collaboration:

At 01:47:28 on November 04, 2023 Fermi-LAT detected high-energy emission from GRB 231104A, which was also detected by Fermi-GBM (trigger 720755253.13875 / 231104075, GCN 34937) and Swift (GCN 34938).

The best LAT on-ground location is found to be

RA, Dec = 24.1, 84.0 (degrees, J2000)

with an error radius of 0.7 deg (90 % containment, statistical error only). This was 29 deg from the LAT boresight at the time of the trigger.

The data from the Fermi-LAT show a significant increase in the event rate that is spatially and temporally correlated with the trigger with high significance. The 100 MeV - 1 GeV photon flux in the time interval 0-400 s after the GBM trigger is (6.6 Â± 2.2) E-06 ph/cm2/s.

The estimated integrated photon index above 100 MeV is -2.7 +/- 0.5. The highest-energy photon is a 530 MeV event which is observed 120 seconds after the GBM trigger.

The Fermi-LAT point of contact for this burst is Giacomo Principe (giacomo.principe@ts.infn.it).

The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.


GRB_name: GRB231104A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34944
SUBJECT: GRB 231104A: Swift-XRT refined Analysis
DATE:    23/11/04 16:55:30 GMT
FROM:    Phil Evans at U of Leicester <pae9@star.le.ac.uk>

J.A. Kennea (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U.
Leicester), M. Capalbi (INAF-IASFPA), M. Perri (SSDC & INAF-OAR), V.
D'Elia (SSDC & INAF-OAR), A. Tohuvavohu (U. Toronto), D.N. Burrows
(PSU) and P.A. Evans report on behalf of the Swift-XRT team:

We have analysed 6.6 ks of XRT data for GRB 231104A, from 72 s to 34.5
ks after the  BAT trigger. The data comprise 62 s in Windowed Timing
(WT) mode (the first 9 s were taken while Swift was slewing) with the
remainder in Photon Counting (PC) mode. 

The late-time light curve (from T0+10.9 ks) can be modelled with a
power-law decay with a decay index of alpha=1.08 (+/-0.22).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.93 (+0.28, -0.27). The
best-fitting absorption column is  7.9 (+1.1, -1.0) x 10^22 cm^-2, in
excess of the Galactic value of 1.3 x 10^21 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 9.9 x 10^-11 (3.0 x 10^-10) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      7.9 (+1.1, -1.0) x 10^22 cm^-2
Galactic foreground: 1.3 x 10^21 cm^-2
Excess significance: 12.5 sigma
Photon index:      1.93 (+0.28, -0.27)

If the light curve continues to decay with a power-law decay index of
1.08, the count rate at T+24 hours will be 0.017 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.7 x
10^-12 (5.0 x 10^-12) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01194500.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB231104A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34945
SUBJECT: GRB 231104A: AstroSat CZTI detection
DATE:    23/11/04 17:12:40 GMT
FROM:    Gaurav Waratkar at IIT Bombay <gauravwaratkar@iitb.ac.in>

P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a bright long-duration GRB 231104A which was also detected by Fermi-GBM (Fermi GBM Team, GCN Circ. 34937), and Swift-BAT (Page et al., GCN Circ. 34938).

The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2023-11-04 01:47:40.35 UTC. The measured peak count rate associated with the burst is 1905 (+239, -231) counts/s above the background in the combined data of three quadrants (out of four), with a total of 2144 (+214, -227) counts. The local mean background count rate was 232 (+6, -7) counts/s. Using cumulative rates, we measure a T90 of 5 (+1, -1) s. We note that the total count measurements are affected by a 0.3s housekeeping dead time window that coincided with the burst. We also see a faint second peak, consistent with the light curve from Fermi-GBM and Swift-BAT, which is more prominently seen in the Veto detectors as reported below. However, the peak is too weak to make any contribution to the T90 measurements in the CZT lightcurve.

The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-11-04 01:47:38.43 UTC. The measured peak count rate associated with the burst is 3448 (+108, -118) counts/s above the background in the combined data of all quadrants, with a total of 14749 (+818, -888) counts. The local mean background count rate was 1357 (+7, -8) counts/s. We measure a T90 of 24 (+1, -18) s from the cumulative Veto light curve. This longer T90 arises from a clear detection of the second peak of the GRB.

CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.

CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB231104A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34946
SUBJECT: GRB 231104A: AKO Upper Limit
DATE:    23/11/04 19:20:58 GMT
FROM:    Mohammad Odeh at Al Khatim Observatory M44 <mshodeh@gmail.com>

Mohammad Odeh (Al-Khatim Observatory, AKO, operated by the International
Astronomical Center in Abu Dhabi, UAE) and Nidhal Guessoum (American
University of Sharjah, UAE) report:

We observed the Fermi GRB 231104A field (Fermi GBM team, GCN 34937) with
with our 0.36m f/7.7 robotic telescope on November 4, from 17:12 to 18:22
UT (corresponding to 16.6 hours from the GRB trigger time) using (Ic)
filter. We obtained 24x180 second images.

We do not detect a source within the Swift-XRT error region around the
candidate X-ray source (Page et al., GCN 34938).

The following 5-sigma upper limit is calculated using the ATLAS catalog as
reference:
Ic = 19.7


GRB_name: GRB231103A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34948
SUBJECT: Fermi GRB 231103A: Global MASTER-Net observations report
DATE:    23/11/04 21:31:35 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-SAAO robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 231103A ( Fermi GBM team, GCN 34934) errorbox  1 days 13914 sec after notice time and 1 days 13948 sec after trigger time at 2023-11-04 18:33:59 UT, with upper limit up to  19.5 mag. The observations began at zenith distance = 32 deg. The sun  altitude  is -17.7 deg. 

The galactic latitude b = -62 deg., longitude l = 301 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2294659

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

  100379 | 2023-11-04 18:33:59 |         MASTER-SAAO | (00h 48m 05.20s , -55d 59m 13.2s) |   C |    60 | 18.1 |        
  100470 | 2023-11-04 18:35:30 |         MASTER-SAAO | (01h 02m 13.02s , -56d 00m 21.6s) |   C |    60 | 17.9 |        
  100550 | 2023-11-04 18:36:50 |         MASTER-SAAO | (00h 45m 39.68s , -54d 04m 42.2s) |   C |    60 | 17.9 |        
  100642 | 2023-11-04 18:38:22 |         MASTER-SAAO | (00h 59m 18.30s , -54d 06m 09.5s) |   C |    60 | 16.9 |        
  100722 | 2023-11-04 18:39:42 |         MASTER-SAAO | (00h 50m 32.32s , -57d 53m 12.0s) |   C |    60 | 16.6 |        
  100813 | 2023-11-04 18:41:12 |         MASTER-SAAO | (01h 05m 34.52s , -57d 52m 15.4s) |   C |    60 | 17.4 |        
  100903 | 2023-11-04 18:42:43 |         MASTER-SAAO | (00h 43m 33.08s , -52d 12m 15.4s) |   C |    60 | 17.1 |        
  100983 | 2023-11-04 18:44:02 |         MASTER-SAAO | (00h 56m 41.87s , -52d 11m 49.5s) |   C |    60 | 17.8 |        
  101073 | 2023-11-04 18:45:33 |         MASTER-SAAO | (01h 11m 34.45s , -54d 06m 01.8s) |   C |    60 | 17.8 |        
  101153 | 2023-11-04 18:46:53 |         MASTER-SAAO | (01h 25m 15.58s , -54d 04m 38.8s) |   C |    60 | 17.4 |        
  101244 | 2023-11-04 18:48:23 |         MASTER-SAAO | (00h 20m 41.61s , -55d 57m 53.2s) |   C |    60 | 18.1 |        
  101323 | 2023-11-04 18:49:43 |         MASTER-SAAO | (00h 35m 06.42s , -55d 59m 02.0s) |   C |    60 | 18.1 |        
  101414 | 2023-11-04 18:51:14 |         MASTER-SAAO | (00h 47m 51.52s , -56d 00m 07.4s) |   C |    60 | 18.0 |        
  101494 | 2023-11-04 18:52:34 |         MASTER-SAAO | (01h 02m 17.63s , -56d 00m 07.2s) |   C |    60 | 17.4 |        
  101574 | 2023-11-04 18:53:54 |         MASTER-SAAO | (00h 45m 36.77s , -54d 04m 35.5s) |   C |    60 | 17.2 |        
  101665 | 2023-11-04 18:55:25 |         MASTER-SAAO | (00h 59m 15.26s , -54d 05m 54.2s) |   C |    60 | 17.6 |        
  101745 | 2023-11-04 18:56:44 |         MASTER-SAAO | (00h 50m 34.14s , -57d 52m 15.6s) |   C |    60 | 17.1 |        
  101835 | 2023-11-04 18:58:15 |         MASTER-SAAO | (01h 05m 31.65s , -57d 53m 04.8s) |   C |    60 | 17.6 |        
  101915 | 2023-11-04 18:59:35 |         MASTER-SAAO | (00h 43m 29.81s , -52d 10m 03.6s) |   C |    60 | 18.8 |        
  102006 | 2023-11-04 19:01:06 |         MASTER-SAAO | (00h 56m 38.27s , -52d 11m 07.4s) |   C |    60 | 18.4 |        
  102090 | 2023-11-04 19:02:30 |         MASTER-SAAO | (01h 11m 28.41s , -54d 06m 08.1s) |   C |    60 | 18.0 |        
  102180 | 2023-11-04 19:04:00 |         MASTER-SAAO | (01h 25m 13.83s , -54d 06m 05.7s) |   C |    60 | 17.6 |        
  102260 | 2023-11-04 19:05:20 |         MASTER-SAAO | (00h 20m 42.61s , -55d 57m 57.1s) |   C |    60 | 17.8 |        
  102340 | 2023-11-04 19:06:40 |         MASTER-SAAO | (00h 35m 00.69s , -55d 59m 37.9s) |   C |    60 | 18.5 |        
  102431 | 2023-11-04 19:08:11 |         MASTER-SAAO | (00h 47m 56.37s , -55d 58m 10.0s) |   C |    60 | 18.6 |        
  102511 | 2023-11-04 19:09:30 |         MASTER-SAAO | (01h 02m 08.10s , -55d 58m 57.3s) |   C |    60 | 18.8 |        
  102601 | 2023-11-04 19:11:01 |         MASTER-SAAO | (00h 45m 32.38s , -54d 03m 51.1s) |   C |    60 | 18.7 |        
  102681 | 2023-11-04 19:12:21 |         MASTER-SAAO | (00h 59m 16.65s , -54d 04m 56.3s) |   C |    60 | 18.9 |        
  102772 | 2023-11-04 19:13:52 |         MASTER-SAAO | (00h 50m 26.68s , -57d 53m 45.1s) |   C |    60 | 18.7 |        
  102863 | 2023-11-04 19:15:23 |         MASTER-SAAO | (01h 05m 35.49s , -57d 53m 43.3s) |   C |    60 | 18.7 |        
  102943 | 2023-11-04 19:16:43 |         MASTER-SAAO | (00h 43m 31.08s , -52d 10m 08.2s) |   C |    60 | 18.5 |        
  103034 | 2023-11-04 19:18:14 |         MASTER-SAAO | (00h 56m 34.06s , -52d 11m 33.8s) |   C |    60 | 18.3 |        
  103114 | 2023-11-04 19:19:34 |         MASTER-SAAO | (01h 11m 32.86s , -54d 04m 11.9s) |   C |    60 | 18.4 |        
  103205 | 2023-11-04 19:21:04 |         MASTER-SAAO | (01h 25m 04.73s , -54d 04m 55.3s) |   C |    60 | 18.7 |        
  103285 | 2023-11-04 19:22:24 |         MASTER-SAAO | (00h 20m 38.65s , -55d 57m 19.5s) |   C |    60 | 19.0 |        
  103375 | 2023-11-04 19:23:55 |         MASTER-SAAO | (00h 35m 01.28s , -55d 58m 30.0s) |   C |    60 | 18.6 |        
  103455 | 2023-11-04 19:25:14 |         MASTER-SAAO | (01h 15m 05.16s , -55d 59m 28.4s) |   C |    60 | 18.4 |        
  103546 | 2023-11-04 19:26:45 |         MASTER-SAAO | (01h 29m 20.63s , -55d 57m 55.9s) |   C |    60 | 18.3 |        
  103636 | 2023-11-04 19:28:16 |         MASTER-SAAO | (00h 21m 53.42s , -57d 51m 21.9s) |   C |    60 | 18.4 |        
  103716 | 2023-11-04 19:29:36 |         MASTER-SAAO | (00h 36m 50.52s , -57d 52m 23.0s) |   C |    60 | 18.8 |        
  103807 | 2023-11-04 19:31:06 |         MASTER-SAAO | (00h 53m 25.90s , -59d 46m 31.6s) |   C |    60 | 18.7 |        
  103886 | 2023-11-04 19:32:26 |         MASTER-SAAO | (01h 09m 13.38s , -59d 47m 38.3s) |   C |    60 | 19.0 |        
  103977 | 2023-11-04 19:33:57 |         MASTER-SAAO | (00h 19m 37.16s , -54d 03m 39.3s) |   C |    60 | 19.1 |        
  104057 | 2023-11-04 19:35:16 |         MASTER-SAAO | (00h 33m 15.26s , -54d 05m 07.0s) |   C |    60 | 19.1 |        
  104148 | 2023-11-04 19:36:48 |         MASTER-SAAO | (01h 08m 13.21s , -52d 10m 43.1s) |   C |    60 | 19.1 |        
  104240 | 2023-11-04 19:38:19 |         MASTER-SAAO | (01h 21m 17.37s , -52d 09m 45.3s) |   C |    60 | 19.2 |        
  104319 | 2023-11-04 19:39:39 |         MASTER-SAAO | (01h 18m 58.93s , -57d 53m 35.1s) |   C |    60 | 18.8 |        
  104411 | 2023-11-04 19:41:11 |         MASTER-SAAO | (01h 34m 08.78s , -57d 53m 34.5s) |   C |    60 | 18.7 |        
  104491 | 2023-11-04 19:42:30 |         MASTER-SAAO | (01h 15m 00.67s , -55d 57m 36.8s) |   C |    60 | 18.5 |        
  104582 | 2023-11-04 19:44:02 |         MASTER-SAAO | (01h 29m 18.81s , -55d 59m 26.5s) |   C |    60 | 18.3 |        
  104673 | 2023-11-04 19:45:32 |         MASTER-SAAO | (00h 21m 52.25s , -57d 51m 04.0s) |   C |    60 | 18.9 |        
  104753 | 2023-11-04 19:46:52 |         MASTER-SAAO | (00h 36m 49.52s , -57d 52m 06.7s) |   C |    60 | 18.8 |        
  104843 | 2023-11-04 19:48:23 |         MASTER-SAAO | (00h 53m 16.53s , -59d 45m 16.1s) |   C |    60 | 18.8 |        
  104923 | 2023-11-04 19:49:43 |         MASTER-SAAO | (01h 09m 18.63s , -59d 46m 23.5s) |   C |    60 | 19.0 |        
  105014 | 2023-11-04 19:51:13 |         MASTER-SAAO | (00h 19m 31.76s , -54d 04m 54.5s) |   C |    60 | 18.6 |        
  105093 | 2023-11-04 19:52:33 |         MASTER-SAAO | (00h 33m 16.45s , -54d 04m 48.7s) |   C |    60 | 19.2 |        
  105184 | 2023-11-04 19:54:04 |         MASTER-SAAO | (01h 08m 14.92s , -52d 09m 37.7s) |   C |    60 | 19.5 |        
  105264 | 2023-11-04 19:55:24 |         MASTER-SAAO | (01h 21m 18.05s , -52d 11m 16.2s) |   C |    60 | 19.5 |        
  105355 | 2023-11-04 19:56:55 |         MASTER-SAAO | (01h 19m 01.73s , -57d 51m 26.8s) |   C |    60 | 19.1 |        
  105435 | 2023-11-04 19:58:14 |         MASTER-SAAO | (01h 34m 00.07s , -57d 52m 23.9s) |   C |    60 | 18.9 |        
  105514 | 2023-11-04 19:59:34 |         MASTER-SAAO | (01h 14m 54.50s , -55d 57m 22.2s) |   C |    60 | 19.1 |        
  105619 | 2023-11-04 20:01:19 |         MASTER-SAAO | (01h 29m 18.65s , -55d 58m 24.7s) |   C |    60 | 19.1 |        
  105699 | 2023-11-04 20:02:39 |         MASTER-SAAO | (00h 21m 43.13s , -57d 52m 37.0s) |   C |    60 | 18.6 |        
  105790 | 2023-11-04 20:04:09 |         MASTER-SAAO | (00h 36m 51.46s , -57d 52m 23.3s) |   C |    60 | 19.0 |        
  105869 | 2023-11-04 20:05:29 |         MASTER-SAAO | (00h 53m 17.74s , -59d 45m 15.4s) |   C |    60 | 18.9 |        
  105961 | 2023-11-04 20:07:01 |         MASTER-SAAO | (01h 09m 11.95s , -59d 47m 01.1s) |   C |    60 | 19.0 |        
  106052 | 2023-11-04 20:08:32 |         MASTER-SAAO | (00h 19m 35.58s , -54d 02m 43.3s) |   C |    60 | 19.0 |        
  106132 | 2023-11-04 20:09:52 |         MASTER-SAAO | (00h 32m 14.43s , -54d 03m 46.8s) |   C |    60 | 19.0 |        
  106223 | 2023-11-04 20:11:23 |         MASTER-SAAO | (01h 08m 10.21s , -52d 09m 11.5s) |   C |    60 | 19.0 |        
  106303 | 2023-11-04 20:12:43 |         MASTER-SAAO | (01h 21m 18.10s , -52d 10m 15.4s) |   C |    60 | 19.2 |        
  106393 | 2023-11-04 20:14:13 |         MASTER-SAAO | (01h 18m 53.89s , -57d 53m 04.3s) |   C |    60 | 18.5 |        
  106484 | 2023-11-04 20:15:44 |         MASTER-SAAO | (01h 34m 02.61s , -57d 52m 46.8s) |   C |    60 | 18.5 |        
  106564 | 2023-11-04 20:17:03 |         MASTER-SAAO | (00h 41m 35.25s , -50d 16m 46.0s) |   C |    60 | 19.3 |        
  106654 | 2023-11-04 20:18:34 |         MASTER-SAAO | (00h 54m 08.61s , -50d 15m 02.8s) |   C |    60 | 19.3 |        
  106734 | 2023-11-04 20:19:54 |         MASTER-SAAO | (00h 16m 58.41s , -52d 08m 19.0s) |   C |    60 | 18.4 |        
  106825 | 2023-11-04 20:21:24 |         MASTER-SAAO | (00h 30m 04.44s , -52d 09m 31.0s) |   C |    60 | 19.0 |        
  106904 | 2023-11-04 20:22:44 |         MASTER-SAAO | (00h 21m 07.37s , -59d 46m 04.0s) |   C |    60 | 19.2 |        
  106995 | 2023-11-04 20:24:15 |         MASTER-SAAO | (00h 36m 56.76s , -59d 44m 33.0s) |   C |    60 | 19.1 |        
  107075 | 2023-11-04 20:25:35 |         MASTER-SAAO | (01h 05m 24.62s , -50d 15m 24.1s) |   C |    60 | 19.3 |        
  107165 | 2023-11-04 20:27:05 |         MASTER-SAAO | (01h 17m 49.62s , -50d 16m 02.4s) |   C |    60 | 19.5 |        
  107245 | 2023-11-04 20:28:25 |         MASTER-SAAO | (00h 56m 40.30s , -61d 39m 32.1s) |   C |    60 | 19.0 |        
  107325 | 2023-11-04 20:29:45 |         MASTER-SAAO | (01h 13m 25.52s , -61d 40m 41.4s) |   C |    60 | 19.0 |        
  107416 | 2023-11-04 20:31:16 |         MASTER-SAAO | (01h 23m 27.45s , -59d 45m 16.8s) |   C |    60 | 19.0 |        
  107587 | 2023-11-04 20:34:07 |         MASTER-SAAO | (00h 41m 11.05s , -50d 14m 59.2s) |   C |    60 | 19.4 |        
  107667 | 2023-11-04 20:35:27 |         MASTER-SAAO | (00h 53m 39.84s , -50d 15m 41.7s) |   C |    60 | 19.4 |        
  107757 | 2023-11-04 20:36:57 |         MASTER-SAAO | (00h 17m 01.97s , -52d 07m 57.7s) |   C |    60 | 18.8 |        
  107837 | 2023-11-04 20:38:17 |         MASTER-SAAO | (00h 30m 06.80s , -52d 09m 10.8s) |   C |    60 | 19.4 |        
  107928 | 2023-11-04 20:39:47 |         MASTER-SAAO | (00h 21m 04.50s , -59d 45m 47.4s) |   C |    60 | 18.9 |        
  108018 | 2023-11-04 20:41:18 |         MASTER-SAAO | (00h 36m 55.09s , -59d 45m 56.9s) |   C |    60 | 19.2 |        
  108097 | 2023-11-04 20:42:37 |         MASTER-SAAO | (01h 04m 07.89s , -50d 14m 42.3s) |   C |    60 | 19.5 |        
  108189 | 2023-11-04 20:44:09 |         MASTER-SAAO | (01h 17m 51.31s , -50d 16m 44.4s) |   C |    60 | 19.5 |        
  108269 | 2023-11-04 20:45:29 |         MASTER-SAAO | (00h 56m 35.62s , -61d 38m 14.1s) |   C |    60 | 19.0 |        
  108359 | 2023-11-04 20:46:59 |         MASTER-SAAO | (01h 13m 21.67s , -61d 39m 23.0s) |   C |    60 | 19.1 |        
  108438 | 2023-11-04 20:48:18 |         MASTER-SAAO | (01h 23m 20.98s , -59d 44m 30.4s) |   C |    60 | 19.1 |        
  108609 | 2023-11-04 20:51:09 |         MASTER-SAAO | (00h 40m 02.48s , -50d 16m 11.9s) |   C |    60 | 19.5 |        
  108689 | 2023-11-04 20:52:28 |         MASTER-SAAO | (00h 52m 34.36s , -50d 16m 04.4s) |   C |    60 | 19.4 |        
  108780 | 2023-11-04 20:53:59 |         MASTER-SAAO | (00h 17m 11.16s , -52d 07m 59.9s) |   C |    60 | 19.2 |        
  108859 | 2023-11-04 20:55:19 |         MASTER-SAAO | (00h 30m 08.49s , -52d 09m 20.1s) |   C |    60 | 19.5 |        
  108951 | 2023-11-04 20:56:50 |         MASTER-SAAO | (00h 21m 16.72s , -59d 43m 37.0s) |   C |    60 | 18.7 |        
  109030 | 2023-11-04 20:58:10 |         MASTER-SAAO | (00h 36m 56.57s , -59d 44m 40.3s) |   C |    60 | 19.1 |        
  109121 | 2023-11-04 20:59:41 |         MASTER-SAAO | (01h 03m 42.75s , -50d 14m 18.9s) |   C |    60 | 19.3 |        
  109211 | 2023-11-04 21:01:11 |         MASTER-SAAO | (01h 16m 20.36s , -50d 15m 24.5s) |   C |    60 | 19.5 |        
  109291 | 2023-11-04 21:02:31 |         MASTER-SAAO | (00h 54m 25.41s , -61d 39m 50.6s) |   C |    60 | 19.0 |        
  109382 | 2023-11-04 21:04:01 |         MASTER-SAAO | (01h 11m 22.74s , -61d 39m 33.8s) |   C |    60 | 19.0 |        
  109461 | 2023-11-04 21:05:21 |         MASTER-SAAO | (01h 21m 25.85s , -59d 44m 13.6s) |   C |    60 | 19.0 |        
  109552 | 2023-11-04 21:06:52 |         MASTER-SAAO | (01h 37m 19.41s , -59d 45m 45.6s) |   C |    60 | 19.2 |        
  109723 | 2023-11-04 21:09:42 |         MASTER-SAAO | (00h 39m 43.02s , -61d 37m 13.9s) |   C |    60 | 19.0 |        
  109802 | 2023-11-04 21:11:02 |         MASTER-SAAO | (01h 35m 49.54s , -54d 04m 06.7s) |   C |    60 | 19.0 |        
  110064 | 2023-11-04 21:15:23 |         MASTER-SAAO | (00h 29m 18.96s , -50d 13m 13.1s) |   C |    60 | 19.5 |        
  110224 | 2023-11-04 21:18:04 |         MASTER-SAAO | (00h 50m 56.80s , -48d 20m 34.3s) |   C |    60 | 19.4 |        
  110314 | 2023-11-04 21:19:34 |         MASTER-SAAO | (01h 01m 43.99s , -48d 21m 25.6s) |   C |    60 | 19.4 |        
  110485 | 2023-11-04 21:22:25 |         MASTER-SAAO | (01h 31m 34.54s , -52d 08m 09.8s) |   C |    60 | 19.4 |        
  110735 | 2023-11-04 21:26:35 |         MASTER-SAAO | (00h 40m 00.46s , -61d 37m 53.3s) |   C |    60 | 19.0 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB231104B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34949
SUBJECT: GRB 231104B: Fermi GBM Final Real-time Localization
DATE:    23/11/04 23:21:14 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 23:10:39 UT on 4 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231104B (trigger 720832244.521916 / 231104966).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 10.9, Dec = -41.8 (J2000 degrees, equivalent to J2000 00h 43m, -41d 47'), with a statistical uncertainty of 3.3 degrees.

The angle from the Fermi LAT boresight is 124.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231104966/quicklook/glg_skymap_all_bn231104966.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231104966/quicklook/glg_healpix_all_bn231104966.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231104966/quicklook/glg_lc_medres34_bn231104966.gif


GRB_name: GRB231104A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34950
SUBJECT: GRB 231104A: Fermi GBM Observation
DATE:    23/11/05 05:31:07 GMT
FROM:    sumanbala2210@gmail.com

S. Bala (USRA) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 01:47:28.14 UT on 04 November 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 231104A (trigger 720755253/231104075).
which was also detected by Swift BAT (K. L. Page et al. 2023, GCN 34938) and 
Fermi LAT (G. Principe. et al. 2023, GCN 34943).
The Fermi GBM on-ground location is consistent with the Swift BAT position.

The angle from the Fermi LAT boresight is 32 degrees.

The GBM light curve Consist of three distinguishable pick with a duration (T90)
of about 44 s (50-300 keV). The time-averaged spectrum
from T0-3.6 to T0+62.0 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is -1.07 +/- 0.01 and the cutoff energy,
parameterized as Epeak, is 539 +/- 22 keV.

The event fluence (10-1000 keV) in this time interval is
(5.59 +/- 0.06)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+3.6 s in the 10-1000 keV band is 2 +/- 0.2 ph/s/cm^2.

A Band function fits the spectrum equally well
with Epeak= 490 +/- 20 keV, alpha = -1.05 +/- 0.02 and beta = -2.6 +/- 0.2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB231104A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34951
SUBJECT: GRB 231104A: NOT upper limit
DATE:    23/11/05 11:47:50 GMT
FROM:    Zipei Zhu at NAOC <zpzhu@nao.cas.cn>

Z. Zhu, D. Xu (NAOC), D.B. Malesani (Radboud Univ. and DAWN/NBI), A. de Ugarte Postigo (OCA-CNRS), Z. Gray (NOT) report on behalf of a larger collaboration: 

We observed the field of GRB 231104A detected by Swift (Page et al., GCN 34938) and Fermi (Fermi GBM team, GCN 34937) using the the 2.56 m Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. Observations started at 01:57:16 UT on 2023-11-05, i.e., ~ 1.0 day after the Swift/BAT trigger, and 9x200 s Sloan i-filter images were obtained.

No optical source is detected within or at the border of the Swift/XRT enhanced error circle (Goad et al., GCN 34940) down to upper limits of i > 24.2 mag (3-sigma), calibrated with the nearby Pan-STARRS stars and not corrected for Galactic extinction.


GRB_name: GRB231104A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34955
SUBJECT: GRB 231104A: 3.6m DOT optical upper limit
DATE:    23/11/06 18:02:21 GMT
FROM:    Rahul Gupta at Aryabhatta Research Institute of Observational Sciences (ARIES) India <rahulbhu.c157@gmail.com>

Rahul Gupta, Amit K. Ror, Amar Aryan, and S. B. Pandey (ARIES) report on
behalf of a larger collaboration:

We observed the field of GRB 231104A detected by Fermi (Fermi GBM team, GCN
34937; Principe et al., GCN 34943), Swift (Page et al., GCN 34938), and
AstroSat (Navaneeth et al., GCN 34945) using the 3.6m Devasthal Optical
Telescope of ARIES Nainital. We have taken multiple frames having an
exposure time of 100 sec in the r and i filters, respectively. We do not
find any evidence of an afterglow candidate inside the Swift/XRT enhanced
error circle (Goad et al., GCN 34940), consistent with other non-detections
(Strausbaugh et al., GCN 34939; Kuin et al., GCN 34941; Odeh et al., GCN
34946; and Zhu et al., GCN 34951). We obtained the limiting mag of ~ 24 mag
(r-band) at ~ 0.9 days post-detection.

The limiting magnitudes quoted are not corrected for the Galactic
extinction in the direction of the burst. Photometric calibration is
performed using the standard stars from the Pan-STARRS catalog.

This circular may be cited. 3.6m Devasthal Optical Telescope (DOT) is
the recently commissioned facility in the Northern Himalayan region of
India (long:79 41 04E, lat:29 21 40N, alt:2540m) owned and operated by the
Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital (
https://www.aries.res.in). Authors of this GCN circular thankfully
acknowledge consistent support from the staff members to run and maintain
the 3.6m DOT.


GRB_name: GRB231106A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34956
SUBJECT: GRB 231106A: Fermi GBM Final Real-time Localization
DATE:    23/11/06 18:24:51 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 18:13:23 UT on 6 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231106A (trigger 720987208.394416 / 231106759).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 113.8, Dec = 25.6 (J2000 degrees, equivalent to J2000 07h 35m, 25d 36'), with a statistical uncertainty of 3.4 degrees.

The angle from the Fermi LAT boresight is 120.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231106759/quicklook/glg_skymap_all_bn231106759.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231106759/quicklook/glg_healpix_all_bn231106759.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231106759/quicklook/glg_lc_medres34_bn231106759.gif


GRB_name: GRB231104A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34957
SUBJECT: GRB 231104A: NuSTAR Observation of the prompt emission
DATE:    23/11/06 19:21:51 GMT
FROM:    Brian Grefenstette at Caltech/NuSTAR <bwgref@srl.caltech.edu>

B. Grefenstette reports on behalf of the NuSTAR Search for INteresting Gamma-ray Signals (SINGS) working group:

The NuSTAR SINGS working group reports the discovery of prompt emission from a potential GRB 231104A in the NuSTAR CsI anti-coincidence shields and the CdZnTe imagers. This GRB was identified through a blind search using the CsI shield rates. Details of the search algorithm will be described in a future paper. 

The CsI data are recorded at 1 Hz and show a broad burst with multiple peaks. The initial NuSTAR trigger had a T0 of 2023-11-04T01:47:31, though offline analysis shows that a initial rise in the shield of 2023-11-04T01:47:37, which is consistent with the onset time reported by Ferm GBM (Bala et al, GCN Circ 34950). Peak 1-sec count rates were ~4,000 counts per second in both the FPMA and FPMB shield units. Typical background rates are ~1,000 counts per second. The burst was detected in both the CdZnTe detectors as well as in the shields.

Using the localization from Swift (Palmer et al, GCN Circ 34938):

 RA(J2000) = 01h 35m 09s
 Dec(J2000) = +83d 47' 27"

â€¦the burst was ~100-degrees from the instrument boresight.

The main burst lasts for ~6-s. Two narrow (<1-s) peaks can be seen in both the 1-Hz CsI shield rates and in the CdZnTe detectors.

The automated light curve report for this GRB, discovery report, off-line analysis of the shield data, and the CdZnTe lightcurves can be found here:

https://nustarsoc.caltech.edu/NuSTAR_Public/grbs/reports/2023/231104A/

Information on NuSTAR SINGS can be found here: 

https://nustarsoc.caltech.edu/NuSTAR_Public/grbs/

NuSTAR is a NASA Small Explorer mission led by Caltech and managed by JPL for NASAâ€™s Science Mission Directorate in Washington. 


GRB_name: GRB231104A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34958
SUBJECT: GRB 231104A: Wendelstein Optical/Infrared Observations
DATE:    23/11/06 20:45:59 GMT
FROM:    m.busmann@physik.lmu.de

Malte Busman (LMU), Daniel Gruen (LMU), Brendan Oâ€™Connor (CMU), Julius Gassert (LMU), Lei Hu (CMU), Antonella Palmese (CMU), Christoph Ries (LMU), Arno Riffeser (LMU/MPE), Michael Schmidt (LMU), Ananya Shankar (LMU):

We observed the position of GRB 231104A (Fermi GBM team, GCN 34937; Page et al., GCN 34938) with the 2m Fraunhofer telescope at Wendelstein Observatory, Germany. Observations were obtained using the 3kk imager in the r, z, and K bands simultaneously starting on 2023-11-06 at 12:09:53 UT with a total exposure of 6,021 seconds.

At the position of the XRT source (Goad et al., GCN 34940) we do not detect any source within 15â€  to depth r> 23.6 and  K>21.0 AB mag at 2.4 days after the GRB trigger. The magnitudes are not corrected for Milky Way extinction and the photometry was calibrated against nearby stars in the PS1 and 2MASS catalogs.

We thank the staff of the Wendelstein Observatory for obtaining these observations.


GRB_name: GRB231106A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34959
SUBJECT: Fermi GRB 231106A: Global MASTER-Net observations report
DATE:    23/11/06 22:01:20 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-Tavrida robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB 231106A ( Fermi GBM team, GCN 34956) errorbox  7435 sec after notice time and 7476 sec after trigger time at 2023-11-06 20:18:00 UT, with upper limit up to  19.0 mag. The observations began at zenith distance = 68 deg. The sun  altitude  is -58.5 deg. 

The galactic latitude b = 21 deg., longitude l = 194 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2296397

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

    7507 | 2023-11-06 20:18:00 |      MASTER-Tavrida | (07h 18m 58.76s , +28d 01m 31.6s) |   C |    60 | 16.6 |        
    7579 | 2023-11-06 20:19:12 |      MASTER-Tavrida | (07h 11m 43.66s , +26d 07m 24.0s) |   C |    60 | 16.1 |        
    8169 | 2023-11-06 20:29:02 |      MASTER-Tavrida | (07h 27m 01.04s , +29d 55m 54.0s) |   C |    60 | 17.4 |        
    8317 | 2023-11-06 20:31:30 |      MASTER-Tavrida | (07h 36m 13.30s , +28d 00m 34.7s) |   C |    60 | 15.6 |        
    8390 | 2023-11-06 20:32:43 |      MASTER-Tavrida | (07h 45m 13.60s , +28d 02m 01.0s) |   C |    60 | 13.5 |        
    8610 | 2023-11-06 20:36:22 |      MASTER-Tavrida | (07h 18m 54.71s , +28d 00m 53.6s) |   C |    60 | 17.7 |        
    9277 | 2023-11-06 20:47:30 |      MASTER-Tavrida | (07h 28m 03.37s , +28d 00m 48.0s) |   C |    60 | 17.8 |        
    9351 | 2023-11-06 20:48:43 |      MASTER-Tavrida | (07h 11m 38.63s , +26d 07m 42.0s) |   C |    60 | 18.0 |        
    9423 | 2023-11-06 20:49:56 |      MASTER-Tavrida | (07h 20m 32.94s , +26d 06m 27.4s) |   C |    60 | 17.8 |        
    9642 | 2023-11-06 20:53:35 |      MASTER-Tavrida | (07h 28m 30.97s , +26d 08m 26.4s) |   C |    60 | 17.5 |        
    9714 | 2023-11-06 20:54:47 |      MASTER-Tavrida | (07h 37m 30.51s , +26d 07m 36.6s) |   C |    60 | 17.3 |        
    9788 | 2023-11-06 20:56:01 |      MASTER-Tavrida | (07h 21m 38.45s , +24d 12m 21.0s) |   C |    60 | 17.4 |        
    9861 | 2023-11-06 20:57:14 |      MASTER-Tavrida | (07h 30m 29.86s , +24d 12m 54.8s) |   C |    60 | 17.0 |        
    9935 | 2023-11-06 20:58:28 |      MASTER-Tavrida | (07h 27m 01.91s , +29d 55m 58.0s) |   C |    60 | 18.5 |        
   10007 | 2023-11-06 20:59:40 |      MASTER-Tavrida | (07h 36m 15.07s , +29d 54m 58.4s) |   C |    60 | 18.2 |        
   10159 | 2023-11-06 21:02:12 |      MASTER-Tavrida | (07h 24m 04.95s , +22d 19m 29.7s) |   C |    60 | 17.1 |        
   10234 | 2023-11-06 21:03:27 |      MASTER-Tavrida | (07h 36m 06.69s , +28d 02m 41.0s) |   C |    60 | 18.2 |        
   10306 | 2023-11-06 21:04:39 |      MASTER-Tavrida | (07h 45m 14.82s , +28d 01m 51.3s) |   C |    60 | 17.7 |        
   10379 | 2023-11-06 21:05:52 |      MASTER-Tavrida | (07h 38m 17.32s , +24d 12m 47.6s) |   C |    60 | 17.3 |        
   10452 | 2023-11-06 21:07:05 |      MASTER-Tavrida | (07h 47m 07.78s , +24d 13m 19.4s) |   C |    60 | 16.2 |        
   10526 | 2023-11-06 21:08:19 |      MASTER-Tavrida | (07h 18m 57.19s , +28d 02m 21.1s) |   C |    60 | 18.3 |        
   11903 | 2023-11-06 21:31:16 |      MASTER-Tavrida | (07h 27m 56.23s , +28d 02m 55.0s) |   C |    60 | 18.3 |        
   11975 | 2023-11-06 21:32:28 |      MASTER-Tavrida | (07h 11m 40.50s , +26d 07m 34.7s) |   C |    60 | 18.6 |        
   12048 | 2023-11-06 21:33:41 |      MASTER-Tavrida | (07h 20m 28.35s , +26d 06m 44.0s) |   C |    60 | 18.5 |        
   12121 | 2023-11-06 21:34:54 |      MASTER-Tavrida | (07h 31m 55.79s , +22d 19m 23.2s) |   C |    60 | 18.1 |        
   12193 | 2023-11-06 21:36:06 |      MASTER-Tavrida | (07h 40m 32.06s , +22d 21m 04.8s) |   C |    60 | 18.2 |        
   12266 | 2023-11-06 21:37:19 |      MASTER-Tavrida | (07h 37m 26.81s , +26d 07m 27.4s) |   C |    60 | 18.7 |        
   12338 | 2023-11-06 21:38:31 |      MASTER-Tavrida | (07h 30m 29.80s , +24d 14m 40.3s) |   C |    60 | 18.5 |        
   12411 | 2023-11-06 21:39:44 |      MASTER-Tavrida | (07h 26m 57.61s , +29d 55m 51.6s) |   C |    60 | 18.9 |        
   12483 | 2023-11-06 21:40:56 |      MASTER-Tavrida | (07h 36m 10.40s , +29d 57m 03.1s) |   C |    60 | 18.7 |        
   12628 | 2023-11-06 21:43:21 |      MASTER-Tavrida | (07h 24m 02.93s , +22d 18m 52.3s) |   C |    60 | 18.3 |        
   12702 | 2023-11-06 21:44:35 |      MASTER-Tavrida | (07h 45m 14.98s , +28d 01m 29.2s) |   C |    60 | 18.8 |        
   12774 | 2023-11-06 21:45:47 |      MASTER-Tavrida | (07h 47m 05.00s , +24d 15m 07.1s) |   C |    60 | 18.5 |        
   12848 | 2023-11-06 21:47:00 |      MASTER-Tavrida | (07h 27m 58.96s , +28d 01m 19.4s) |   C |    60 | 18.9 |        
   13142 | 2023-11-06 21:51:54 |      MASTER-Tavrida | (07h 20m 26.86s , +26d 08m 02.8s) |   C |    60 | 19.0 |        
   13215 | 2023-11-06 21:53:08 |      MASTER-Tavrida | (07h 40m 28.08s , +22d 21m 25.6s) |   C |    60 | 18.7 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB231104A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34961
SUBJECT: GRB 231104A: FRAM-ORM optical limit
DATE:    23/11/07 13:35:15 GMT
FROM:    Martin Jelinek at Astro.Inst-AVCR,Ondrejov <martin.jelinek@asu.cas.cz>

Alzbeta Malenakova, Martin Jelinek and Jan Strobl (ASU CAS Ondrejov, CZ),
Sergey Karpov, Martin Masek, Petr Janecek, Jakub Jurysek,
Jan Ebr, Ronan Cunniffe, Petr Travnicek and Michael Prouza
(Institute of Physics, Prague, CZ)

report:

The 25cm robotic telescope FRAM-ORM at La Palma (Spain) reacted robotically
to the Fermi-GBM/Swift/Fermi-LAT/AstroSat CZTI alert of GRB 231104A (Bala
et al., GCNC 34937, Page et al., GCNC 34938 and Goad et al., GCNC 34940,
Principe. et al. 2023, GCNC 34943, Navaneeth et al., GCNC 34945), obtaining
a series of 20s unfiltered images starting at 01:48:10.3 UT, i.e. 31.3s
post trigger, covering the third gamma ray episode of the GRB.

We do not detect any new source in comparison to Atlas Refcat 2.0 (Tonry et
al., 2018) neither in single images (detection limit r'>17.6) nor in a
combined 40x20s frame (mean exp time 960s post trigger, with a limit
r'>18.6) similarly to Strausbaugh et al. (GCNC 34939), Kuin et al. (GCNC
34941), Odeh et al. (GCNC 34946), Zhu et al. (GCNC 34951), Gupta et al.
(GCNC 34955) and Busman et al. (GCNC 34958).


GRB_name: GRB231104A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34964
SUBJECT: GRB 231104A: Swift-BAT refined analysis
DATE:    23/11/08 01:28:51 GMT
FROM:    Sibasish Laha at GSFC <sibasish.laha@nasa.gov>

M. Stamatikos (OSU), S. D. Barthelmy (GSFC),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (U Tampa),C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Parsotan (GSFC/UMBC),
T. Sakamoto (AGU),(i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 231104A (trigger #1194500)
(Page et al., GCN Circ. 34938).  The BAT ground-calculated position is
RA, Dec = 23.824, 83.794 deg which is
   RA(J2000)  =  01h 35m 17.8s
   Dec(J2000) = +83d 47' 38.7"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 89%.

The BAT  light curve shows a complex structure with a duration of ~ 80 sec.
T90 (15-350 keV) is 46.77 +- 1.54 sec (estimated error including systematics).

The time-averaged spectrum from T-13.39 to T+55.84 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.24 +- 0.03.  The fluence in the 15-150 keV band is 1.3 +- 0.0 x 10^-05 erg/cm2.
The 1-sec peak photon flux measured from T+0.24 sec in the 15-150 keV band
is 24.8 +- 0.6 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/1194500/BA/


GRB_name: GRB231106A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34965
SUBJECT: GRB 231106A: CALET Gamma-Ray Burst Monitor detection
DATE:    23/11/08 07:00:36 GMT
FROM:    Yuta Kawakubo at Louisiana State University <kawakubo1@lsu.edu>

T. Sakamoto, A. Yoshida, S. Sugita (AGU), Y. Kawakubo (LSU),
K. Yamaoka (Nagoya U), S. Nakahira (JAXA), Y. Asaoka (ICRR), 
S. Torii, Y. Akaike, K. Kobayashi (Waseda U), Y. Shimizu,
T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC),
M. L. Cherry (LSU), S. Ricciarini (U of Florence),
P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long GRB 231106A (Fermi GBM Final Real-time Localization: 
Fermi GBM team, GCN Circ. 34956) triggered the CALET Gamma-ray
Burst Monitor (CGBM) at 18:12:50.43 UTC on 6 November 2023
(http://cgbm.calet.jp/cgbm_trigger/flight/1383329517).
The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure that starts
at T-8.5 sec, peaks at T+38.1 sec, and ends at T+80.9 sec.
The T90 duration measured by the SGM data are 61.6 +/- 6.3 
sec (40-1000 keV).

The ground-processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1383329517/index.html

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at Waseda University.


GRB_name: GRB231106A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34966
SUBJECT: GRB 231106A: AstroSat CZTI detection
DATE:    23/11/08 09:10:39 GMT
FROM:    Gaurav Waratkar at IIT Bombay <gauravwaratkar@iitb.ac.in>

P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a GRB 231106A which was also detected by Fermi - GBM (Fermi GBM Team, GCN Circ. 34956) and CALET (Sakamoto et al., GCN Circ. 34965).

The source was clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-11-06 18:13:23.15 UTC. The measured peak count rate associated with the burst is 213 (+67, -26) counts/s above the background in the combined data of all quadrants, with a total of 3452 (+1277, -1014) counts. The local mean background count rate was 1235 (+4, -5) counts/s. We measure a T90 of 54 (+22, -11) s from the cumulative Veto light curve.

CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.

CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB231108A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34969
SUBJECT: GRB 231108A: Fermi GBM Final Real-time Localization
DATE:    23/11/08 21:14:37 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 21:03:09 UT on 8 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231108A (trigger 721170194.442402 / 231108877).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 104.8, Dec = 50.5 (J2000 degrees, equivalent to J2000 06h 59m, 50d 30'), with a statistical uncertainty of 18.6 degrees.

The angle from the Fermi LAT boresight is 102.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231108877/quicklook/glg_skymap_all_bn231108877.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231108877/quicklook/glg_healpix_all_bn231108877.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231108877/quicklook/glg_lc_medres34_bn231108877.gif


GRB_name: GRB231108A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34970
SUBJECT: Fermi GRB 231108A: Global MASTER-Net observations report
DATE:    23/11/09 00:01:29 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-Tavrida robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB 231108A ( Fermi GBM team, GCN 34969) errorbox  3 sec after notice time and 40 sec after trigger time at 2023-11-08 21:03:50 UT, with upper limit up to  18.5 mag. The observations began at zenith distance = 55 deg. The sun  altitude  is -62.2 deg. 

MASTER-Kislovodsk robotic telescope  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB 231108A errorbox  691 sec after notice time and 728 sec after trigger time at 2023-11-08 21:15:18 UT, with upper limit up to  19.0 mag. The observations began at zenith distance = 41 deg. The sun  altitude  is -63.2 deg. 

The galactic latitude b = 22 deg., longitude l = 166 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2298284

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

      71 | 2023-11-08 21:03:50 |      MASTER-Tavrida | (08h 41m 45.01s , +58d 27m 23.1s) |   C |    60 | 17.3 |        
     147 | 2023-11-08 21:05:06 |      MASTER-Tavrida | (07h 07m 08.35s , +48d 54m 26.2s) |   C |    60 | 18.1 |        
     218 | 2023-11-08 21:06:17 |      MASTER-Tavrida | (07h 19m 20.09s , +48d 56m 14.2s) |   C |    60 | 17.6 |        
     619 | 2023-11-08 21:12:58 |      MASTER-Tavrida | (08h 21m 12.60s , +39d 27m 23.9s) |   C |    60 | 18.0 |        
     691 | 2023-11-08 21:14:10 |      MASTER-Tavrida | (08h 31m 33.20s , +39d 26m 06.7s) |   C |    60 | 17.7 |        
     759 | 2023-11-08 21:15:18 |   MASTER-Kislovodsk | (07h 23m 14.82s , +54d 32m 01.4s) |   C |    60 | 17.7 |        
     759 | 2023-11-08 21:15:18 |   MASTER-Kislovodsk | (07h 30m 25.80s , +54d 09m 17.2s) |   C |    60 | 18.4 |        
     839 | 2023-11-08 21:16:38 |   MASTER-Kislovodsk | (09h 07m 35.74s , +56d 21m 29.1s) |   C |    60 | 16.4 |        
     919 | 2023-11-08 21:17:58 |   MASTER-Kislovodsk | (07h 17m 38.12s , +56d 24m 36.4s) |   C |    60 | 17.2 |        
     919 | 2023-11-08 21:17:58 |   MASTER-Kislovodsk | (07h 25m 15.46s , +56d 01m 24.9s) |   C |    60 | 17.8 |        
     921 | 2023-11-08 21:18:00 |      MASTER-Tavrida | (07h 11m 59.70s , +54d 38m 22.4s) |   C |    60 | 18.5 |        
     999 | 2023-11-08 21:19:18 |   MASTER-Kislovodsk | (07h 25m 51.74s , +56d 01m 28.8s) |   C |    60 | 13.1 |        
    1155 | 2023-11-08 21:21:54 |      MASTER-Tavrida | (07h 25m 54.07s , +54d 36m 55.6s) |   C |    60 | 17.9 |        
    1160 | 2023-11-08 21:21:58 |   MASTER-Kislovodsk | (08h 38m 59.74s , +58d 15m 35.4s) |   C |    60 | 16.4 |        
    1160 | 2023-11-08 21:21:59 |   MASTER-Kislovodsk | (08h 46m 31.94s , +57d 52m 18.1s) |   C |    60 | 17.0 |        
    1227 | 2023-11-08 21:23:06 |      MASTER-Tavrida | (07h 18m 07.07s , +52d 44m 34.1s) |   C |    60 | 18.1 |        
    1299 | 2023-11-08 21:24:18 |      MASTER-Tavrida | (07h 31m 18.06s , +52d 43m 06.2s) |   C |    60 | 18.0 |        
    1372 | 2023-11-08 21:25:31 |      MASTER-Tavrida | (07h 05m 56.42s , +56d 31m 58.2s) |   C |    60 | 18.3 |        
    1443 | 2023-11-08 21:26:42 |      MASTER-Tavrida | (07h 20m 17.36s , +56d 31m 56.2s) |   C |    60 | 18.2 |        
    1515 | 2023-11-08 21:27:54 |      MASTER-Tavrida | (07h 23m 34.52s , +60d 20m 59.5s) |   C |    60 | 18.0 |        
    1586 | 2023-11-08 21:29:05 |      MASTER-Tavrida | (07h 39m 47.47s , +60d 20m 21.4s) |   C |    60 | 17.8 |        
    1657 | 2023-11-08 21:30:16 |      MASTER-Tavrida | (07h 54m 11.87s , +60d 19m 38.5s) |   C |    60 | 17.7 |        
    1729 | 2023-11-08 21:31:28 |      MASTER-Tavrida | (08h 10m 24.47s , +60d 20m 04.0s) |   C |    60 | 17.6 |        
    1803 | 2023-11-08 21:32:42 |      MASTER-Tavrida | (07h 24m 08.22s , +50d 50m 33.9s) |   C |    60 | 18.0 |        
    1841 | 2023-11-08 21:33:20 |   MASTER-Kislovodsk | (07h 34m 21.20s , +50d 43m 19.2s) |   C |    60 | 16.6 |        
    1841 | 2023-11-08 21:33:20 |   MASTER-Kislovodsk | (07h 41m 01.95s , +50d 21m 23.1s) |   C |    60 | 17.4 |        
    1875 | 2023-11-08 21:33:54 |      MASTER-Tavrida | (07h 36m 46.36s , +50d 49m 37.0s) |   C |    60 | 18.0 |        
    1921 | 2023-11-08 21:34:40 |   MASTER-Kislovodsk | (07h 51m 19.72s , +44d 59m 47.5s) |   C |    60 | 16.8 |        
    1921 | 2023-11-08 21:34:40 |   MASTER-Kislovodsk | (07h 57m 16.39s , +44d 37m 42.0s) |   C |    60 | 17.5 |        
    1949 | 2023-11-08 21:35:08 |      MASTER-Tavrida | (08h 55m 55.56s , +56d 33m 53.9s) |   C |    60 | 17.9 |        
    2021 | 2023-11-08 21:36:20 |      MASTER-Tavrida | (09h 10m 18.52s , +56d 33m 19.6s) |   C |    60 | 18.2 |        
    2097 | 2023-11-08 21:37:36 |      MASTER-Tavrida | (07h 42m 19.94s , +45d 09m 22.0s) |   C |    60 | 18.2 |        
    2162 | 2023-11-08 21:38:41 |   MASTER-Kislovodsk | (07h 39m 52.01s , +48d 48m 22.7s) |   C |    60 | 16.5 |        
    2162 | 2023-11-08 21:38:41 |   MASTER-Kislovodsk | (07h 46m 17.64s , +48d 25m 48.5s) |   C |    60 | 17.1 |        
    2169 | 2023-11-08 21:38:48 |      MASTER-Tavrida | (07h 53m 44.90s , +45d 08m 34.5s) |   C |    60 | 17.8 |        
    2242 | 2023-11-08 21:40:01 |      MASTER-Tavrida | (07h 30m 07.03s , +48d 55m 08.5s) |   C |    60 | 17.6 |        
    2313 | 2023-11-08 21:41:12 |      MASTER-Tavrida | (07h 42m 21.32s , +48d 55m 44.2s) |   C |    60 | 16.0 |        
    2387 | 2023-11-08 21:42:26 |      MASTER-Tavrida | (08h 26m 24.41s , +58d 27m 47.7s) |   C |    60 | 16.1 |        
    2442 | 2023-11-08 21:43:21 |   MASTER-Kislovodsk | (07h 45m 24.66s , +46d 55m 03.8s) |   C |    60 | 16.1 |        
    2442 | 2023-11-08 21:43:21 |   MASTER-Kislovodsk | (07h 51m 43.59s , +46d 32m 21.3s) |   C |    60 | 16.8 |        
    2522 | 2023-11-08 21:44:41 |   MASTER-Kislovodsk | (07h 16m 39.36s , +48d 50m 58.1s) |   C |    60 | 16.5 |        
    2522 | 2023-11-08 21:44:41 |   MASTER-Kislovodsk | (07h 23m 14.68s , +48d 28m 27.8s) |   C |    60 | 17.4 |        
    2700 | 2023-11-08 21:47:39 |   MASTER-Kislovodsk | (08h 38m 03.68s , +60d 10m 24.2s) |   C |    60 | 16.8 |        
    2700 | 2023-11-08 21:47:39 |   MASTER-Kislovodsk | (08h 46m 08.40s , +59d 47m 15.1s) |   C |    60 | 17.1 |        
    2781 | 2023-11-08 21:49:00 |   MASTER-Kislovodsk | (07h 10m 14.57s , +50d 43m 56.5s) |   C |    60 | 17.2 |        
    2781 | 2023-11-08 21:49:00 |   MASTER-Kislovodsk | (07h 17m 04.93s , +50d 20m 54.9s) |   C |    60 | 18.0 |        
    2861 | 2023-11-08 21:50:20 |   MASTER-Kislovodsk | (08h 37m 49.04s , +62d 06m 20.5s) |   C |    60 | 17.3 |        
    2861 | 2023-11-08 21:50:20 |   MASTER-Kislovodsk | (08h 46m 22.33s , +61d 43m 10.1s) |   C |    60 | 18.1 |        
    3598 | 2023-11-08 22:02:37 |      MASTER-Tavrida | (07h 07m 06.37s , +48d 56m 06.0s) |   C |    60 | 17.5 |        
    3670 | 2023-11-08 22:03:48 |      MASTER-Tavrida | (07h 19m 09.33s , +48d 55m 23.7s) |   C |    60 | 18.2 |        
    3996 | 2023-11-08 22:09:15 |      MASTER-Tavrida | (08h 21m 11.38s , +39d 28m 23.8s) |   C |    60 | 17.4 |        
    4068 | 2023-11-08 22:10:27 |      MASTER-Tavrida | (08h 31m 25.38s , +39d 27m 39.7s) |   C |    60 | 16.8 |        
    4284 | 2023-11-08 22:14:03 |   MASTER-Kislovodsk | (07h 39m 42.05s , +48d 51m 53.7s) |   C |    60 | 16.5 |        
    4284 | 2023-11-08 22:14:03 |   MASTER-Kislovodsk | (07h 46m 17.94s , +48d 29m 56.6s) |   C |    60 | 17.0 |        
    4565 | 2023-11-08 22:18:44 |   MASTER-Kislovodsk | (08h 15m 52.11s , +37d 24m 43.5s) |   C |    60 | 17.0 |        
    4565 | 2023-11-08 22:18:44 |   MASTER-Kislovodsk | (08h 21m 17.67s , +37d 01m 28.1s) |   C |    60 | 17.7 |        
    4646 | 2023-11-08 22:20:05 |   MASTER-Kislovodsk | (07h 45m 27.64s , +46d 55m 38.6s) |   C |    60 | 17.2 |        
    4726 | 2023-11-08 22:21:25 |   MASTER-Kislovodsk | (07h 16m 39.80s , +48d 53m 09.4s) |   C |    60 | 17.5 |        
    4726 | 2023-11-08 22:21:25 |   MASTER-Kislovodsk | (07h 23m 18.67s , +48d 29m 33.5s) |   C |    60 | 18.5 |        
    4807 | 2023-11-08 22:22:46 |   MASTER-Kislovodsk | (08h 34m 10.45s , +45d 00m 17.2s) |   C |    60 | 17.4 |        
    4807 | 2023-11-08 22:22:46 |   MASTER-Kislovodsk | (08h 40m 14.69s , +44d 37m 05.3s) |   C |    60 | 18.4 |        
    4908 | 2023-11-08 22:24:26 |   MASTER-Kislovodsk | (08h 37m 40.72s , +60d 14m 38.6s) |   C |    60 | 17.5 |        
    4908 | 2023-11-08 22:24:27 |   MASTER-Kislovodsk | (08h 46m 15.67s , +59d 50m 31.7s) |   C |    60 | 18.6 |        
    4988 | 2023-11-08 22:25:47 |   MASTER-Kislovodsk | (08h 38m 01.60s , +60d 14m 42.4s) |   C |    60 | 12.9 |        
    5068 | 2023-11-08 22:27:07 |   MASTER-Kislovodsk | (08h 39m 18.47s , +60d 14m 44.7s) |   C |    60 | 12.7 |        
    5229 | 2023-11-08 22:29:47 |   MASTER-Kislovodsk | (09h 07m 27.65s , +58d 17m 04.4s) |   C |    60 | 17.6 |        
    5309 | 2023-11-08 22:31:08 |   MASTER-Kislovodsk | (08h 02m 58.59s , +64d 03m 13.4s) |   C |    60 | 17.6 |        
    5309 | 2023-11-08 22:31:08 |   MASTER-Kislovodsk | (08h 12m 44.36s , +63d 38m 25.5s) |   C |    60 | 18.4 |        
    5389 | 2023-11-08 22:32:27 |   MASTER-Kislovodsk | (08h 17m 56.79s , +43d 08m 54.7s) |   C |    60 | 17.4 |        
    5389 | 2023-11-08 22:32:28 |   MASTER-Kislovodsk | (08h 23m 50.17s , +42d 45m 50.1s) |   C |    60 | 18.2 |        
    5678 | 2023-11-08 22:37:17 |   MASTER-Kislovodsk | (08h 15m 59.32s , +37d 27m 13.7s) |   C |    60 | 16.7 |        
    5678 | 2023-11-08 22:37:17 |   MASTER-Kislovodsk | (08h 21m 23.66s , +37d 04m 11.4s) |   C |    60 | 17.6 |        
    5783 | 2023-11-08 22:39:02 |   MASTER-Kislovodsk | (08h 21m 27.77s , +37d 04m 10.7s) |   C |    60 | 12.5 |        
    7153 | 2023-11-08 23:01:52 |   MASTER-Kislovodsk | (07h 16m 32.57s , +48d 54m 57.5s) |   C |    60 | 17.1 |        
    7153 | 2023-11-08 23:01:52 |   MASTER-Kislovodsk | (07h 23m 16.95s , +48d 32m 15.3s) |   C |    60 | 18.0 |        
    7233 | 2023-11-08 23:03:12 |   MASTER-Kislovodsk | (08h 34m 11.17s , +45d 02m 42.3s) |   C |    60 | 17.0 |        
    7233 | 2023-11-08 23:03:12 |   MASTER-Kislovodsk | (08h 40m 19.67s , +44d 40m 22.7s) |   C |    60 | 18.1 |        
    7313 | 2023-11-08 23:04:32 |   MASTER-Kislovodsk | (08h 37m 30.25s , +60d 15m 20.3s) |   C |    60 | 17.5 |        
    7313 | 2023-11-08 23:04:32 |   MASTER-Kislovodsk | (08h 46m 11.06s , +59d 51m 10.8s) |   C |    60 | 18.4 |        
    7398 | 2023-11-08 23:05:57 |   MASTER-Kislovodsk | (07h 17m 05.18s , +50d 24m 16.2s) |   C |    60 | 18.3 |        
    7398 | 2023-11-08 23:05:57 |   MASTER-Kislovodsk | (07h 10m 06.06s , +50d 47m 43.7s) |   C |    60 | 17.4 |        
    7525 | 2023-11-08 23:08:04 |   MASTER-Kislovodsk | (08h 37m 12.79s , +62d 10m 55.8s) |   C |    60 | 17.6 |        
    7525 | 2023-11-08 23:08:04 |   MASTER-Kislovodsk | (08h 46m 26.67s , +61d 46m 55.0s) |   C |    60 | 18.3 |        
    7685 | 2023-11-08 23:10:44 |   MASTER-Kislovodsk | (09h 07m 21.85s , +58d 21m 24.3s) |   C |    60 | 17.6 |        
    7765 | 2023-11-08 23:12:04 |   MASTER-Kislovodsk | (08h 02m 45.90s , +64d 05m 19.3s) |   C |    60 | 17.9 |        
    7765 | 2023-11-08 23:12:04 |   MASTER-Kislovodsk | (08h 12m 37.53s , +63d 41m 30.2s) |   C |    60 | 18.7 |        
    7845 | 2023-11-08 23:13:24 |   MASTER-Kislovodsk | (08h 17m 51.40s , +43d 10m 18.8s) |   C |    60 | 17.9 |        
    7845 | 2023-11-08 23:13:24 |   MASTER-Kislovodsk | (08h 23m 50.55s , +42d 48m 05.9s) |   C |    60 | 19.0 |        
    7925 | 2023-11-08 23:14:44 |   MASTER-Kislovodsk | (08h 18m 19.23s , +43d 10m 19.8s) |   C |    60 | 12.4 |        
    8113 | 2023-11-08 23:17:52 |   MASTER-Kislovodsk | (08h 55m 39.82s , +45d 01m 39.6s) |   C |    60 | 15.9 |        
    8193 | 2023-11-08 23:19:12 |   MASTER-Kislovodsk | (07h 57m 05.13s , +43d 10m 45.3s) |   C |    60 | 16.0 |        
    8194 | 2023-11-08 23:19:12 |   MASTER-Kislovodsk | (08h 03m 05.80s , +42d 48m 44.1s) |   C |    60 | 16.7 |        
    8285 | 2023-11-08 23:20:44 |   MASTER-Kislovodsk | (08h 37m 25.88s , +64d 03m 39.7s) |   C |    60 | 15.4 |        
    8285 | 2023-11-08 23:20:44 |   MASTER-Kislovodsk | (08h 47m 15.02s , +63d 39m 31.6s) |   C |    60 | 15.8 |        
    8366 | 2023-11-08 23:22:04 |   MASTER-Kislovodsk | (07h 32m 20.23s , +62d 12m 43.9s) |   C |    60 | 15.4 |        
    8366 | 2023-11-08 23:22:05 |   MASTER-Kislovodsk | (07h 41m 38.41s , +61d 49m 17.0s) |   C |    60 | 16.1 |        
    9869 | 2023-11-08 23:47:08 |   MASTER-Kislovodsk | (09h 07m 19.25s , +58d 22m 40.1s) |   C |    60 | 16.9 |        
    9949 | 2023-11-08 23:48:28 |   MASTER-Kislovodsk | (08h 02m 39.15s , +64d 05m 19.2s) |   C |    60 | 16.7 |        
    9949 | 2023-11-08 23:48:28 |   MASTER-Kislovodsk | (08h 12m 32.76s , +63d 41m 18.6s) |   C |    60 | 17.1 |        
   10029 | 2023-11-08 23:49:48 |   MASTER-Kislovodsk | (08h 17m 53.96s , +43d 09m 43.9s) |   C |    60 | 17.2 |        
   10029 | 2023-11-08 23:49:48 |   MASTER-Kislovodsk | (08h 23m 56.08s , +42d 47m 03.5s) |   C |    60 | 18.2 |        
   10109 | 2023-11-08 23:51:08 |   MASTER-Kislovodsk | (08h 38m 39.91s , +43d 10m 47.4s) |   C |    60 | 17.1 |        
   10109 | 2023-11-08 23:51:08 |   MASTER-Kislovodsk | (08h 44m 40.28s , +42d 48m 02.0s) |   C |    60 | 17.9 |        
   10189 | 2023-11-08 23:52:28 |   MASTER-Kislovodsk | (08h 55m 33.63s , +45d 02m 33.8s) |   C |    60 | 17.1 |        
   10270 | 2023-11-08 23:53:49 |   MASTER-Kislovodsk | (07h 57m 05.41s , +43d 12m 03.4s) |   C |    60 | 16.5 |        
   10270 | 2023-11-08 23:53:49 |   MASTER-Kislovodsk | (08h 03m 08.76s , +42d 49m 11.7s) |   C |    60 | 17.2 |        
   10350 | 2023-11-08 23:55:09 |   MASTER-Kislovodsk | (08h 37m 17.03s , +64d 05m 34.1s) |   C |    60 | 16.1 |        
   10350 | 2023-11-08 23:55:09 |   MASTER-Kislovodsk | (08h 47m 10.35s , +63d 41m 13.8s) |   C |    60 | 16.6 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB231109A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34974
SUBJECT: GRB 231109A: Fermi GBM Final Localization
DATE:    23/11/09 19:57:25 GMT
FROM:    Christian Malacaria at ISSI <cmalacaria.astro@gmail.com>

The Fermi GBM team reports the detection of a likely SHORT GRB.

At 06:34:01.34 UT on 9 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 231109A (trigger 721204446 / 231109274).

The on-ground calculated location, using the Fermi GBM trigger data, is RA
= 173.0, Dec = 50.7 (J2000 degrees, equivalent to J2000 11h 32m, 50d 42â€™),
with a statistical uncertainty of 6.8 degrees.

The angle from the Fermi LAT boresight is 143 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231109274/quicklook/glg_skymap_all_bn231109274.png

The HEALPix FITS file, including the estimated localization systematic, can
be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231109274/quicklook/glg_healpix_all_bn231109274.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231109274/quicklook/glg_lc_medres34_bn231109274.gif


GRB_name: GRB231110A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34977
SUBJECT: GRB 231110A: Swift detection of a burst
DATE:    23/11/10 21:35:09 GMT
FROM:    Jamie Kennea at Penn State <jak51@psu.edu>


V. D'Elia (SSDC & INAF-OAR), E. Ambrosi (INAF-IASFPA),
A. D'Ai (INAF-IASFPA), S. Dichiara (PSU), J.D. Gropp (PSU),
J. A. Kennea (PSU), A. Melandri (INAF-OAR) and M. A. Williams (PSU)
report on behalf of the Neil Gehrels Swift Observatory Team:

At 21:19:34 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 231110A (trigger=1195733).  Swift did not slew immediately 
to the burst due to an observing constraint. 
The BAT on-board calculated location is 
RA, Dec 356.296, +82.621 which is 
   RA(J2000) = 23h 45m 11s
   Dec(J2000) = +82d 37' 16"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single-peaked
structure with a duration of about 20 sec.  The peak count rate
was ~2800 counts/sec (15-350 keV), at ~1 sec after the trigger. 

Due to an observing constraint, Swift will not slew until T0+50.7
minutes. There will be no XRT or UVOT data until this time. 

Burst Advocate for this burst is V. D'Elia (valerio.delia AT ssdc.asi.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB231110A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34979
SUBJECT: GRB231110A: WFST Observation and upper limits
DATE:    23/11/11 14:16:02 GMT
FROM:    Tianrui Sun at Purple Mountain Obs,CAS <trsun@pmo.ac.cn>

Tian-Rui Sun, Jin-Jun Geng, and Zhen-Qiang Li report on behalf of the WFST Collaboration:

Following the detection of GRB 231110A by SWIFT (Dâ€™Elia et al., GCN 34977) and MASTER (Lipunov et al., GCN 34978), we carried out image observations using the newly deployed Wide Field Survey Telescope (WFST Collaboration; arXiv:2306.07590) at Lenghu Astronomical Observation Base (Qinghai province, China) to search and follow up its afterglow in the BAT error box.

We observed the target position with 13x60s and 27x90s exposure in i-band starting from 10 Nov 2023, UTC 05:59:01, about 39.45 minutes after the burst.

After stacking the individual exposures (5x90s) to enhance observation depth at low altitude, we found two possible candidates:

RA            | DEC             | i-magnitude |magerr |limit 
23:45:02.3407 | +82:38:43.067   | 21.6953     |0.0957 |22.3909
23:45:18.0531 | +82:37:18.403   | 22.0166     |0.1286 |22.3909

We used the PanStarrs DR1 (Flewelling,2020) catalog as the magnitude reference for calibration.


GRB_name: GRB231111A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34981
SUBJECT: GRB 231111A: Swift detection of a burst with an optical counterpart
DATE:    23/11/11 14:33:33 GMT
FROM:    Jamie Kennea at Penn State <jak51@psu.edu>


A. Melandri (INAF-OAR), E. Ambrosi (INAF-IASFPA),
A. D'Ai (INAF-IASFPA), S. Dichiara (PSU), J.D. Gropp (PSU),
J. A. Kennea (PSU) and D. M. Palmer (LANL) report on behalf of the
Neil Gehrels Swift Observatory Team:

At 14:17:19 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 231111A (trigger=1195887).  Swift slewed immediately to
the event. The BAT on-board calculated location is 
RA, Dec 290.234, +52.447 which is 
  RA(J2000) = 19h 20m 56s
  Dec(J2000) = +52d 26' 49"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  Due to a telemetry outage, there is no
immediately available BAT lightcurve information.  However the
trigger information indicates an initial count rate of
3100 counts/s (25-100 keV) on a 1 second timescale. 

The XRT began observing the field at 14:18:59.3 UT, 99.6 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 290.1915, 52.4383 which is equivalent to:
   RA(J2000)  = 19h 20m 45.96s
   Dec(J2000) = +52d 26' 17.9"
with an uncertainty of 5.5 arcseconds (radius, 90% containment). This
location is 98 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy. 

UVOT took a finding chart exposure of 238 seconds with the U filter starting
164 seconds after the BAT trigger. There is a candidate afterglow in the
rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 19:20:45.24 = 290.18848
  DEC(J2000) = +52:26:10.5  =  52.43626
with a 90%-confidence error radius of about 0.62 arc sec. This position is 9.9
arc sec. from the center of the XRT error circle. The estimated magnitude is
16.51 with a 1-sigma error of about  0.14. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.117. 

Burst Advocate for this burst is A. Melandri (andrea.melandri AT inaf.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB231111A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34982
SUBJECT: GRB 231111A: Nanshan/HMT optical observations
DATE:    23/11/11 16:34:46 GMT
FROM:    Dong Xu at NAOC/CAS <dxu@nao.cas.cn>

S.Q. Jiang, Z.P. Zhu, S.Y. Fu, J. An, X. Liu, T.H. Lu, D. Xu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report:

We observed the optical afterglow of GRB 231111A detected by Swift (Melandri et al., GCN 34981) using the HMT-0.5m telescope located at Nanshan, Xinjiang, China. Observations started at 14:18:35 UT on 2023-11-11, i.e., 75 s after the Swift/BAT trigger, and we obtained a serise of 3x20, 3x40, 4x60, 4x90, 4x120, 4x200 s frames without any filter.

The optical afterglow has been decaying during our observations from m(r)~16.04 mag @85 s post-burst to m(r)~18.77 mag @2734 s post-burst, roughly in a powerlaw with a decay index of ~ -0.7, calibrated with the nearby PanSTAR field in the Sloan r-filter and the magnitude is not corrected for Galactic extinction.


GRB_name: GRB231111A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34983
SUBJECT: GRB 231111A: MASTER OT earlier detection
DATE:    23/11/11 16:40:06 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, P.Balanutsa (Lomonosov MSU), N.Budnev, O.Gress (ISU, API),A.Sankovich,
D.Vlasenko, Yu.Tselik, Ya.Kechin, E.Gorbovskoy, A.Kuznetsov, K.Zhirkov, N.Tiurina,
A.Chasovnikov, I.Gorbunov, D.Zimnukhov, V.Senik, V.Topolev, D.Cheryasov, A.Sosnovskij, V.Senik (Lomonosov Moscow State University, SAI, Physics Department),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
D. Buckley (South African Astronomical Observatory),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico FelixAguilar OAFA),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov (Blagoveschensk Educational State University)

MASTER Global robotic net (http://observ.pereplet.ru Lipunov et al.,2010,Advances in Astronomy,2010,30L)
started (Lipunov et al. GCN 34980)
Swift GRB 231111A (Ttrigger=14:17:19UT, Melandri al. GCN 34981, XRTstart=99s after trigger time)
17s after notice time at 14:17:57UT.

We detected optical counterpart (Melandri et al. GCN 34981) of GRB 231111A
MASTER OT J192045.23+522610.1 from first image at rise stage.
We see Smooth Optical Self-similar Emission of this Gamma-Ray Bursts
(SOSS-emission, Lipunov et al. 2017, ApJ, 845, id9 https://ui.adsabs.harvard.edu/abs/2017ApJ...845...52L/abstract )

Observations and reduction will be continued.


GRB_name: GRB231111A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34984
SUBJECT: GRB231111A: GIT confirmation of the optical afterglow
DATE:    23/11/11 17:31:04 GMT
FROM:    Anirudh Salgundi <salgundi.anirudh@gmail.com>

R. Kumar, A. Salgundi, V. Swain, V. Bhalerao (IIT Bombay), S. Barway, G. C. Anupama (IIA), K. Angail (IAO)

We observed the field of GRB 231111A detected by Swift (Melandri et al., GCN 34981) with 0.7m GROWTH-India Telescope (GIT). We started the observation at 14:30:41 UT on 2023-11-11, i.e., 14.46 minutes after the Swift trigger. We obtained multiple frames in the g' and r' bands, and have a clear detection at the position reported by Swift/XRT (Melandri et al., GCN 34981). The details of the photometry are given in the below table:

----------------------------------------------------------------------

JD (mid) | t-t0 (minutes) | Filter | Exposure (s) | Magnitude (AB) |

----------------------------------------------------------------------


2460260.105395619 | 14.46  | r' | 200 | 17.88 +/- 0.05 |
2460260.108019142 | 18.23  | g' | 200 | 18.35 +/- 0.04 |
2460260.110584214 | 21.92  | r' | 200 | 18.24 +/- 0.04 |
2460260.113222184 | 25.72  | g' | 200 | 18.64 +/- 0.04 |
2460260.204636255 | 157.36 | r' | 300 | 19.52 +/- 0.07 |
2460260.208421405 | 162.81 | g' | 300 | 19.99 +/- 0.07 |

----------------------------------------------------------------------

Based on our photometry, we find that the source is consistently fading with power-law decay rate of 0.69 +/- 0.04 in both g' and r' band. Our results are consistent with magnitudes and decay rate obtained by Nanshan/HMT (Jiang et al. GCN 34982). The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction.

The GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/.


GRB_name: GRB231111A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34985
SUBJECT: GRB231111A: YAHPT Observations
DATE:    23/11/11 18:04:47 GMT
FROM:    Tianrui Sun at Purple Mountain Obs,CAS <trsun@pmo.ac.cn>

Tian-Rui Sun, Jin-Jun Geng, Jian Chen and Lei Hu report on behalf of the YAHPT team:


Following the detection of GRB 231111A by SWIFT (Melandri et al., GCN 34981), MASTER (Lipunov et al., GCN 34980, GCN 34983) and Nanshan/HMT (Jiang et al. GCN 34982), we conducted observations using the Yaoan High Precision Telescope at Yaoan Astronomy Observation Station (YAHPT; Yunnan province, China) to search and follow up its afterglow around the SWIFT/UVOT detection.


Our follow-up imaging obervations adopted 180s exposure in Rc-band starting from 11 Nov 2023, UTC 14:47:12.70, about 1792.99 seconds after the burst. 
The YAHPT observations detected a declining optical afterglow from 18.34 +/- 0.07 mag to 18.98 +/- 0.12 mag in Rc band throughout our observations. 
We monitored this object until it is technically unobservable for our telescope, at about 4755 second after the burst.


We used the USNO B1.0 catalog (R1mag) as the magnitude reference for calibration.

[Editor's Note: The subject was modified at the user's request to list the correct GRB name.]


GRB_name: GRB231110A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34986
SUBJECT: GRB 231110A: Swift-XRT afterglow detection
DATE:    23/11/11 20:48:23 GMT
FROM:    Phil Evans at U of Leicester <pae9@star.le.ac.uk>

A.P. Beardmore (U. Leicester), J.P. Osborne (U. Leicester), M. Perri
(SSDC & INAF-OAR), V. D'Elia (SSDC & INAF-OAR), B. Sbarufatti
(INAF-OAB), A. Tohuvavohu (U. Toronto), D.N. Burrows (PSU), J. D. Gropp
(PSU) and P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT
team:

Swift-XRT has performed follow-up observations of the
Swift-BAT-detected burst GRB 231110A, collecting 10 ks of Photon
Counting (PC) mode data between T0+8.9 ks and T0+61.1 ks. 

Four uncatalogued X-ray sources are detected consistent with being
within 296 arcsec of the Swift-BAT position, of which one ("Source 2")
is believed to be the afterglow.  The position of this source is RA,
Dec=356.2752, +82.6447 which is equivalent to:

RA (J2000): 23:45:6.05
Dec(J2000): +82:38:40.9

with an uncertainty of 5.1 arcsec (radius, 90% confidence).  This
position is 85 arcsec from the Swift-BAT position.  There is evidence
that the source may be fading, however we cannot constrain the decay at
the current time

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01195733.
The results of the full analysis of the XRT observations are available
at https://www.swift.ac.uk/ToO_GRBs/01195733.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB231110A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34987
SUBJECT: GRB 231110A: SAO RAS optical observations
DATE:    23/11/11 21:59:36 GMT
FROM:    Moskvitin Alexander at SAO RAS <mosk@sao.ru>

A. S. Moskvitin and O. A. Maslennikova (SAO RAS)
report on behalf of the GRB follow-up team.

We observed the field of Swift GRB 231110A (D'Elia et al., GCN #34977)
with the 1-m telescope of SAO RAS equipped with the CCD photometer.
We obtained 8 x 300 sec. images in Rc band on November 10,
22:09:05--22:55:32 UT (t_mid - T0 = 1.21224 hours).

Following the non-detection of OT by MASTER team (Lipunov et al.,
GCN #34978) we also did not detect any significant source within
the probable XRT error circle (Beardmore et al., GCN #34986)
down to the limiting magnitude R_lim = 22.9. We should note
the presence of the first object mentioned by Sun et al. (GCN #34979)
near the XRT error circle. The brightness of this object is
R = 22.50 +/- 0.24.

Preliminary photometry is based on nearby USNO-B1 stars (R2 mag).
Magnitudes are not corrected for MW extinction.


GRB_name: GRB231110A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34988
SUBJECT: GRB 231110A: GOTO optical upper limits
DATE:    23/11/11 22:37:18 GMT
FROM:    Ben Gompertz at U of Birmingham <b.gompertz@bham.ac.uk>

B. P. Gompertz, R. Starling, A. Kumar, K. Ackley, M. J. Dyer, J. Lyman, K. Ulaczyk, F. Jimenez-Ibarra, D. O'Neill, D. Steeghs, D. K. Galloway, V. Dhillon, P. O'Brien, G. Ramsay, K. Noysena, R. Kotak, R. P. Breton, L. K. Nuttall, E. Pall'e and D. Pollacco report on behalf of the GOTO collaboration:

The Gravitational-wave Optical Transient Observer (GOTO, Steeghs et al. 2022) performed a targeted observation in response to GRB 231110A (Dâ€™Elia et al., GCN 34977) at 22:26:08 UT on 2023-11-10, 66.5 minutes after trigger. The observation consisted of a 4x90s exposure in the GOTO L-band (400-700 nm).

Images were processed immediately after acquisition using the GOTO pipeline. No optical counterpart is detected at the position of the X-ray afterglow (Beardmore et al., GCN 34986) to a 3-sigma limit of L > 19.9 magnitudes (AB).

Magnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and are not corrected for Galactic extinction.

GOTO (https://goto-observatory.org) is a network of telescopes that is principally funded by the STFC and operated at the Roque de los Muchachos Observatory on La Palma, Spain, and Siding Spring Observatory in NSW, Australia, on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory & Planetarium, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT), the University of Turku, the University of Portsmouth, the University of Manchester and the Instituto de Astrofisica de Canarias (IAC).


GRB_name: GRB231110A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34989
SUBJECT: GRB 231110A: GECAM detection
DATE:    23/11/12 01:01:31 GMT
FROM:    Yue Wang <m18509381757@163.com>

Yue Wang, Shaoli Xiong, Yue Huang report on behalf of the GECAM team:

GECAM-B was triggered in-flight by a long burst, GRB 231110A, at 2023-11-10T21:19:35.100 UTC (T0), which was also observed by Swift/BAT (GCN # 34977).

According to the realtime alert data of GECAM-B, this burst
mainly consists of a long pulse with a duration (T90) of about ~20 sec (20-1000 keV).

The GECAM-B localization is consistent with the Swift/BAT team localization (trigger=1195733) within the error.

The time-averaged spectrum of GECAM-B realtime data shows that it could be
adequately fit by a cut-off power-law with a flux about 1.3E-6 erg/cm^2 in 20-1000 keV. 

We note that these results are based on realtime alert data and thus very preliminary. 
Refined analysis will be reported later.

Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor
(GECAM) mission originally consists of two microsatellites (GECAM-A and GECAM-B)
launched in Dec. 2020. As the third member of GECAM constellation, 
GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. 
GECAM mission is funded by the Chinese Academy of Sciences (CAS).


GRB_name: GRB231111A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34990
SUBJECT: GRB 231111A: GECAM-C detection of a long burst
DATE:    23/11/12 01:02:21 GMT
FROM:    wenlongzhang2018@163.com

Wen-long Zhang, Shaoli Xiong, Yue Huang report on behalf of the GECAM team:

GECAM-C was triggered by a long burst, GRB 231111A, at 2023-11-11T14:17:19.850 UTC (T0), which was also observed by Swift/BAT  ( GCN 34981) . 

According to the realtime alert data, the GECAM-C light curve shows roughly two peaks with a total duration of ~30 sec (20-1000 keV). 
The time-averaged spectrum could be adequately fit by a Band function with a flux about 3.36E-7 erg/cm2 in 20-1000 keV. 

We note that these results are based on realtime alert data and thus very preliminary. Refined analysis will be reported later.

Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM) mission originally consists of two microsatellites (GECAM-A and GECAM-B) launched in Dec. 2020. As the third member of GECAM constellation, GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. GECAM mission is funded by the Chinese Academy of Sciences (CAS).


GRB_name: GRB231111A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34991
SUBJECT: GRB 231111A: Enhanced Swift-XRT position
DATE:    23/11/12 01:50:29 GMT
FROM:    Phil Evans at U of Leicester <pae9@star.le.ac.uk>

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 2772 s of XRT Photon Counting mode data and 5 UVOT
images for GRB 231111A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 290.18884, +52.43571 which is equivalent
to:

RA (J2000): 19h 20m 45.32s
Dec (J2000): +52d 26' 08.6"

with an uncertainty of 2.3 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB231110A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34992
SUBJECT: GRB 231110A: GECAM-B detection (correction)
DATE:    23/11/12 02:26:47 GMT
FROM:    Yue Wang <m18509381757@163.com>

Yue Wang, Shao-Lin Xiong, Yue Huang report on behalf of the GECAM team:

GECAM-B was triggered in-flight by a long burst, GRB 231110A, at 2023-11-10T21:19:35.100 UTC (T0), which was also observed by Swift/BAT (GCN #34977).

According to the realtime alert data of GECAM-B, this burst
mainly consists of a long pulse with a duration (T90) of about ~20 sec (20-1000 keV).

The GECAM-B localization is consistent with the Swift/BAT localization (trigger=1195733) within the error.

The time-averaged spectrum of GECAM-B realtime data from about T0 to T0+4 s could be
adequately fit by a cut-off power-law with a flux about 1.3E-6 erg/cm^2/s in 20-1000 keV. 

We note that these results are based on realtime alert data and thus very preliminary. 
Refined analysis will be reported later.

Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor
(GECAM) mission originally consists of two microsatellites (GECAM-A and GECAM-B)
launched in Dec. 2020. As the third member of GECAM constellation, 
GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. 
GECAM mission is funded by the Chinese Academy of Sciences (CAS).


GRB_name: GRB231111A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34993
SUBJECT: GRB 231111A: GECAM-C detection of a long burst (correction)
DATE:    23/11/12 02:28:22 GMT
FROM:    wenlongzhang2018@163.com

Wen-Long Zhang, Shao-Lin Xiong, Yue Huang report on behalf of the GECAM team:

GECAM-C was triggered by a long burst, GRB 231111A, at 2023-11-11T14:17:19.850 UTC (T0), which was also observed by Swift/BAT (GCN #34981) . 

According to the realtime alert data, the GECAM-C light curve shows roughly two peaks with a total duration of ~30 sec (20-1000 keV). 

The time-averaged spectrum of GECAM-C realtime data from about T0 to T0+20 s could be adequately fit by a cut-off power-law with a flux about 3.3E-7 erg/cm^2/s in 20-1000 keV. 

We note that these results are based on realtime alert data and thus very preliminary. Refined analysis will be reported later.

Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM) mission originally consists of two microsatellites (GECAM-A and GECAM-B) launched in Dec. 2020. As the third member of GECAM constellation, GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. GECAM mission is funded by the Chinese Academy of Sciences (CAS).


GRB_name: GRB231111A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34994
SUBJECT: GRB 231111A: Mondy optical observations
DATE:    23/11/12 03:05:47 GMT
FROM:    Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>

N. Pankov (HSE, IKI),  E. Klunko (ISTP),  A. Pozanenko (IKI), S. Belkin (IKI,HSE) report on behalf of GRB IKI FuN:

We observed  the field of Swift GRB 231111A (Melandri et al. GCN 34981) with AZT-33IK telescope of Mondy observatory  in  R-filter on
2023-11-11 starting (UT) 14:36:53. We detect afterglow   (Melandri et al. GCN 34981; Jiang et al. GCN 34982; Lipunov et al. GCN 34983) within  Enhanced Swift-XRT error circle. 
Preliminary photometry  of first images is following

Date       UT start  t-T0     Exp.   Filter   OT     Err.  UL(3sigma)
                   (mid, days)  (s)
2023-11-11  14:36:53  0.014284  1x120 R       18.24 0.08 20.3

The photometry is based on nearby USNO-B1.0 R2 stars.


GRB_name: GRB231111A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34995
SUBJECT: GRB 231111A: Swift-XRT refined Analysis
DATE:    23/11/12 04:47:24 GMT
FROM:    Phil Evans at U of Leicester <pae9@star.le.ac.uk>

J.P. Osborne (U. Leicester), V. D'Elia (SSDC & INAF-OAR), B. Sbarufatti
(INAF-OAB), A. D'Ai (INAF-IASFPA), D.N. Burrows (PSU), J. D. Gropp
(PSU), S. Dichiara (PSU), K.L. Page (U. Leicester) and P.A. Evans
report on behalf of the Swift-XRT team:

We have analysed 7.3 ks of XRT data for GRB 231111A, from 93 s to 39.7
ks after the  BAT trigger. The data comprise 296 s in Windowed Timing
(WT) mode (the first 5 s were taken while Swift was slewing) with the
remainder in Photon Counting (PC) mode. 

The late-time light curve (from T0+16.2 ks) can be modelled with a
power-law decay with a decay index of alpha=1.03 (+/-0.23).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.47 (+0.10, -0.06). The
best-fitting absorption column is  1.297 (+0.206, -0.027) x 10^21
cm^-2, consistent with the Galactic value of 1.3 x 10^21 cm^-2
(Willingale et al. 2013). The PC mode spectrum has a photon index of
1.98 (+0.19, -0.18) and a best-fitting absorption column of 1.6 (+0.6,
-0.3) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV
flux conversion factor deduced from this spectrum  is 3.5 x 10^-11 (4.6
x 10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.6 (+0.6, -0.3) x 10^21 cm^-2
Galactic foreground: 1.3 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:      1.98 (+0.19, -0.18)

If the light curve continues to decay with a power-law decay index of
1.03, the count rate at T+24 hours will be 0.029 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 10.0 x
10^-13 (1.3 x 10^-12) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01195887.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB231110A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34996
SUBJECT: GRB 231110A: Terskol Zeiss-2000 optical upper limit
DATE:    23/11/12 10:50:05 GMT
FROM:    Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>

N. Pankov (IKI, HSE), I. Sokolov (INASAN, KIAM), A. Buslaeva (INASAN), A. Pozanenko (IKI),  S. Belkin (IKI, HSE)  report on behalf of GRB IKI FuN:

We observed the  Swift GRB 231110A (D'Elia et al., GCN #34977) with Zeiss-2000  telescope of Terskol observatory starting on 2023-11-10 (UTC) 23:25:16. We do not detect any object within Source #2 of XRT probable afterglow (Beardmore et al., GCN 34986). This is cosnistent with non-detection in other observations (Lipunov et al., GCN 34978; Sun et al., GCN 34979; Sun et al., GCN 34985; Moskvitin et al., GCN 34987; Gompertz et al., GCN 34988).  Preliminary photometry of the field is following.

Date       UT start  t-T0     Filter Exp.  OT   Err. UL.  Telescope
                     (mid, days)      (s)
2023-11-10 23:25:16  0.08729  R    28*120  R n/d n/d 22.4 Zeiss-2000

The photometry is based on the nearby USNO-B1.0 stars.


GRB_name: GRB231111A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34997
SUBJECT: GRB 231111A: Osservatorio Astronomico "Nastro Verde" optical observations with detection of an optical counterpart
DATE:    23/11/12 11:03:17 GMT
FROM:    Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy - MPC Code C82 <osservatorionastroverde@gmail.com>

Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy
in a large collaboration with:
M.G. Dainotti (National Astronomical Observatory of Japan), 
Y. Niino (Tokyo University, Institute of Astronomy), 
K. Kalinowski (Aarhus University, Department of Physics and Astronomy),
B. De Simone (Universita' degli Studi Di Salerno)
report: 
Following the Swift trigger no. 1195887 (GCN 34981 A. Melandri et al) from the Swift Burst Alert Telescope (BAT), we pointed at the coordinates RA(J2000)=19h 20m 45.96s: Dec(J2000)=52d 26' 17.9" and started our observations with telescope of Nastro Verde Observatory - Sorrento (Naples), Italy.
Member of: 
AAVSO - American Association of Variable Star Observers.
UAI/SSV - Unione Astrofili Italiani/sezione stelle variabili.
AstroCampania Associazione.

The observations started at 18:00 UT of 2023/11/11, after about 4 hours after the GRB trigger, with light cloud veils that left large spaces of clear sky, with principal telescope  SC 0.35 f/10 with focal reduced + CCD Sbig ST10 XME
I took 13 unfiltered images of 120 sec and 26 unfiltered images of 60 sec . All images, calibrated with masterdark and masterflat have been measured with Thycho Tracker and Astrometrica software
We have detected a faint source at the enhanced position reported by Swift-XRT team (J.P. Osborne et al., GCN 34991 ) 
at following position

RA (J2000)   19 20 45.12
Dec (J2000) +52 26 10.2  

with the following photometry and astrometry:

GRB 23111 KC2023 11 11.82061 19 20 45.12 +52 26 10.2          20.4       C82




Magnitudes were estimated with the GAIA DR2 cat. and are not corrected for galactic dust extinction.

Further observations are encouraged.

The message may be cited.


GRB_name: GRB231106B
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34998
SUBJECT: GRB 231106B: GRBAlpha detection
DATE:    23/11/12 11:28:33 GMT
FROM:    Marianna DafÄÃ­kovÃ¡ at Masaryk University <500025@mail.muni.cz>

M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal,  A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), yyT. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory),  T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.

The short-duration GRB 231106B (Konus/Wind trigger at 2023-11-06 21:19:01.729 UT; INTEGRAL/SPI-ACS peak detection at 2023-11-06 ~21:19:01 UT) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023, A&A, 677, 40; arXiv:2302.10048).

The detection was confirmed at the peak time 2023-11-06 21:19:01 UTC. The T90 duration measured by GRBAlpha is 1 s and the overall significance during T90 reaches 6.8 sigma.

The light curve obtained by GRBAlpha is available here: https://grbalpha.konkoly.hu/static/share/GRB231106B_GCN.pdf

All GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ 
GRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume. 


GRB_name: GRB231111A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  34999
SUBJECT: GRB 231111A: GMG observation upper limit
DATE:    23/11/12 12:30:52 GMT
FROM:    Jirong Mao at Yunnan Obs <jirongmao@mail.ynao.ac.cn>

B.-T. Wang, R.-Z. Li, J. Mao, X. Ding, J.-M. Bai report:

We observed the field of GRB 231111A ( Melandri et al. GCN 34981) by the GMG telescope in Yunnan observatories. The observation began from UT 11:29:03 Nov 12, 2023, about 21.2 hours from the trigger. We could not observe the optical afterglow down to a magnitude limit of R~20.7.


GRB_name: GRB231111A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35001
SUBJECT: GRB 231111A: GMG observation (correction)
DATE:    23/11/12 14:40:17 GMT
FROM:    Rui-Zhi Li at Yunnan Astronomical Observatory, CAS <liruizhi@ynao.ac.cn>

R.-Z. Li, B.-T. Wang, J. Mao, X. Ding, J.-M. Bai (YNAO) report:

We observed the field of GRB 231111A (Melandri et al. GCN 34981) by the GMG telescope in Yunnan observatories. The observation began from UT 11:29:03 Nov 12, 2023, about 21.2 hours from the trigger. The preliminary results are shown as

----------------------------------------------------
UT    filter mag
----------------------------------------------------
2023-11-12T11:29:03.291  R 22.2 Â± 0.4
----------------------------------------------------

We apologize for any inconvenience this may have caused.


GRB_name: GRB231111A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35002
SUBJECT: GRB231111A: Optical follow-up observations with Mephisto
DATE:    23/11/12 15:11:08 GMT
FROM:    Tianrui Sun at Purple Mountain Obs,CAS <trsun@pmo.ac.cn>

Tian-Rui Sun, Xin-Lei Chen, Xiangkun Liu, Yuan-Pei Yang, Tianyu Zhang, Helong Guo, Guowang Du, Haipeng Lei, Brajesh Kumar, Xiaowei Liu report on behalf of the Mephisto Collaboration:

Following the detection of GRB 231111A by SWIFT (Melandri et al., GCN 34981, Osborne et al., GCN 34991 and GCN 34995), MASTER (Lipunov et al., GCN 34980, GCN 34983) , Nanshan/HMT (Jiang et al., GCN 34982), Git (Kumar et al., GCN 34984), YAHPT (Sun et al., GCN 34985), Gecam (Zhang et al, GCN 34990 and 34993), Mondy (Pankov et al., GCN 34994), Terskol Zeiss-2000 (Pankov et al., GCN 34996), Nastro Verde (Dainotti et al., GCN 34997), GMG (Mao et al., GCN 34999, GCN 35001), we conducted observations using the Multi-channel Photometric Survey Telescope (Mephisto) of Yunnan University at Lijiang Observatory (IAU code: 044) of Yunnan Astronomical Observatories, Chinese Academy of Sciences (CAS) to search and follow up its afterglow near SWIFT/UVOT position.

We simultaneously observed the target position with 60s exposure in u/g bands and v/r bands starting from 11 Nov 2023, UTC 14:49:05, about 1905 seconds after the burst.

At the beginning of our observation:
Filter     |Mag  |Magerr | Time                  |reference 
Mu         |19.48| 0.12  | 2023-11-11T14:56:35   |Mephisto u
Mv         |19.13| 0.07  | 2023-11-11T14:49:05   |Mephisto v
Mg         |18.65| 0.04  | 2023-11-11T14:56:35   |Mephisto g
Mr         |18.15| 0.04  | 2023-11-11T14:49:05   |Mephisto r

To do the flux calibration, we chose the exposure with the best image quality as the reference image, and used stars of signal-to-noise ratio (SNR) >30 after removing variables by cross-matching with variable catalogs in each band to scale the flux level to that of the reference image. Atmospheric extinction corrections and instrumental magnitude zero points are applied to the reference image.

Mephisto is a 1.6-m wide-field multi-channel telescope, the first of its type in the world, capable of imaging the same field of view in three optical bands simultaneously. It will yield real-time, high-quality colors of unprecedented accuracy of billions of objects, enable fast and robust classification of variables and transients, and for the first time, deliver a panoramic and panchromatic documentary of our dynamic universe. The on-site telescope assemblage and commissioning were carried out in September 2022, and the first light with the small system of 4 filters (uviz) in dual channels was achieved on October 23, 2022. Mephisto is currently equipped with two commercial Andor iKon-XXL single-chip CCD cameras for the blue and yellow channels. Each camera covers an area about a quarter of the full field-of-view (2Â°in diameter).

[Editor's Note: The subject was modified at the user's request to list the correct GRB name.]


GRB_name: GRB231111A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35003
SUBJECT: GRB 231111A: Leavitt Observatory optical observations
DATE:    23/11/12 17:16:00 GMT
FROM:    leavittob@gmail.com

L. Moretti  and E. Pavoni (Leavitt Observatory), in a large collaboration with:
M.G. Dainotti (National Astronomical Observatory of Japan), 
Y. Niino (Tokyo University, Institute of Astronomy), 
K. Kalinowski (Aarhus University, Department of Physics and Astronomy),
B. De Simone (Universita' degli Studi Di Salerno)
report: 

We imaged the field of GRB 231111A (Lipunov et al., GCN 34980; Melandri  et al., GCN 34981; Jiang et al., GCN 34982; Lipunov et al., GCN 34983; Kumar et al., GCN 34984; Osborne et al., GCN 34991; Wen-Long Zhang et al., GCN 34993; Pankov et al., GCN 34994; Osborne et al., GCN 34995; Ruocco, GCN 34997; Li et al., GCN 35001) with the telescope of Leavitt Observatory, Italy. Member of: 

UAI/SSV - Unione Astrofili Italiani/sezione stelle variabili, GRB section.
ATA - Associazione Tuscolana di Astronomia.

The observations started 189 minutes after the BAT trigger, at 17:26:49 UT on 2023/11/11, with our RC telescope D=250 mm F/D=8.

Weather conditions were medium, with light and variable cloud cover. 

We co-added 15 images of 120 sec each, acquired from 17:26:49 to 18:20:58 UT. All images are R (Cousins) filtered, calibrated with master dark and master flat.

We confirm a fading afterglow in the error box of the astrometrically corrected position measured by Swift-XRT (GCN 34991), at the following coordinates +/- 2 arcsec:

RA(J2000)  =  19h 20m 45.25s
DEC(J2000) = +52d 26' 09.9''

The result of our photometry is:

-------------------------------------------------------------------------
JD_UTC at mid-exposure       mag            Err              Flt   
-------------------------------------------------------------------------
2460260.2464583                      20.1            +/- 0.2            R    
    

Magnitudes were estimated with the Gaia DR3 catalogue (*) and are not corrected for galactic dust extinction.

The message may be cited.

(*) https://gea.esac.esa.int/archive/documentation/GEDR3/Data_processing/chap_cu5pho/cu5pho_sec_photSystem/cu5pho_ssec_photRelations.html


GRB_name: GRB231111A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35004
SUBJECT: GRB 231111A NUTTelA-TAO / BSTI Early Measurements
DATE:    23/11/12 18:00:28 GMT
FROM:    Toktarkhan Komesh at Nazarbayev University <toktarkhan.komesh@nu.edu.kz>

T. Komesh (NU), B. Grossan (UCB, NU), Zh. Maksut (NU), Zh. Abdullayev (NU), M. Krugov (FAI), and E. Abdikamalov (NU) report on behalf of the Energetic Cosmos Laboratory:

The Nazarbayev University Transient Telescope at Assy-Turgen Astrophysical Observatory (NUTTelA-TAO) pointed at GRB231111A on receipt of an automated GCN / BAT position alert, observing in Sloan g', r' and i' bands, with the Burst Simultaneous Three-Channel Imager (BSTI; Grossan, Kumar & Smoot 2019, JHEA, 32, 14).

We started observations at UT 2023-11-11 14:18:02, 43 s after the BAT trigger. Observations were made under partially cloudy conditions. A new and changing source consistent with the XRT position (Osborne 2023, GCN 34991) was detected. Note that these observations provide essentially full-time coverage, simultaneous in all three bands. We report the following photometric values for the OT: 

tc-t0(s)  g'(mag)  r'(mag)    i'(mag)      exposure_time (s)
----       -----    -----     -----            -----
69    16.6      16.3       16.0             52.5
133   16.8      16.3       16.4             75
208   17.1      16.7       16.7             75
283   17.2      16.8       16.8             75
358   17.3      16.9       16.8             75
433   17.5      17.2       17.0             75
508   17.6      17.3       17.2             75
583   17.6      17.4       17.3             75
658   17.7      17.5       17.3             75
733   18.0      17.7       17.3             75
808   17.9      17.7       17.6             75
883   18.1      17.9       17.6             75
958   18.0      17.8       17.7             75
1033  18.0      17.9       17.6             75
1108  18.2      18.0       17.6             75
1183  18.0      18.2       17.9             75
1296  18.4      18.3       18.0            150
1446  18.4      18.2       17.9             150



Uncertainties are estimated at ~ 0.1 mag for all three filters. tc-t0 = trigger time minus image center time. Calibration was done with 5 bright Pan-STARRS catalog stars on our images, and no other analysis or corrections.

We caution the reader that these are preliminary results, without color or other corrections, and will likely change in small measure. Please also note that times are approximate.

----------------------------------
NU = Nazarbayev University, Nur-Sultan, Kazakhstan
UCB = University of California, Berkeley, USA
FAI = Fesenkov Astrophysical Institute, Kazakhstan

This research has been funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP14870504). The NUTTelA-TAO Team acknowledges the support of the staff of the Assy-Turgen Astrophysical Observatory, Almaty, Kazakhstan, and the Fesenkov Astrophysical Institute, Almaty, Kazkhstan.


GRB_name: GRB231110A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35005
SUBJECT: GRB 231110A: AstroSat CZTI detection
DATE:    23/11/12 19:05:57 GMT
FROM:    Gaurav Waratkar at IIT Bombay <gauravwaratkar@iitb.ac.in>

P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long-duration GRB 231110A which was also detected by Swift-BAT (D'Elia et al., GCN Circ. 34977), and GECAM-B (Wang et al., GCN Circ. 34992).

The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2023-11-10 21:19:35.25 UTC. The measured peak count rate associated with the burst is 246 (+54, -49) counts/s above the background in the combined data of all quadrants, with a total of 611 (+135, -146) counts. The local mean background count rate was 290 (+4, -5) counts/s. Using cumulative rates, we measure a T90 of 6 (+2, -2) s.

The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-11-10 21:19:34.93 UTC. The measured peak count rate associated with the burst is 469 (+67, -71) counts/s above the background in the combined data of all quadrants, with a total of 957 (+229, -242) counts. The local mean background count rate was 1167 (+6, -7) counts/s. We measure a T90 of 5 (+3, -2) s from the cumulative Veto light curve.

CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.

CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB231110A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35006
SUBJECT: GRB 231110A: Glowbug gamma-ray detection
DATE:    23/11/13 02:43:32 GMT
FROM:    C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>

C.C. Cheung, M. Kerr, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:

The Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 231110A, which was also detected by Swift/BAT, GECAM-B, and AstroSat/CZTI (GCN 34977, 34992, 35005). 

Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-11-10 21:19:32.008 with a duration of 8.2 s and a total significance of about 38 sigma.  The light curve comprises the single peak observed by Swift/BAT, GECAM-B, and AstroSat/CZTI.

Using a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=1.2 and a cutoff energy ("Epeak") of 271 keV.  The modeled 10-10000 keV fluence is 2.4e-06 erg/cm^2.

The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.

Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC.  It was launched on 2023 March 15 aboard the Department of Defense Space Test Programâ€™s STP-H9 to the ISS.  The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.

[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006

Distribution Statement A: Approved for public release.  Distribution is unlimited.


GRB_name: GRB231111A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35007
SUBJECT: GRB 231111A: TNG tentative redshift
DATE:    23/11/13 10:40:29 GMT
FROM:    Paolo D'Avanzo at INAF-OAB <pda.davanzo@gmail.com>

P. D'Avanzo (INAF-OAB), V. D'Elia (ASI/SSDC & INAF/OAR), D. B. Malesani (DAWN/NBI & Radboud Univ.), A. Melandri (INAF/OAR) , M. Cecconi, C. P. Padilla-Torres (INAF/TNG) report on behalf of the CIBO collaboration:

We report observations of GRB 231111A (Melandri et al. GCN Circ. 34981) with the 3.6m Telescopio Nazionale Galileo (TNG) equipped with DOLORES.

We acquired a spectrum of the optical source reported by Melandri et al. (GCN Circ. 34981). We obtained 2x1200 s with the LR-B grism, for a total exposure of 2400 s, covering the wavelength range 3500 - 8000 AA. The observations started on 2023-11-11 at 19:31:33 UT (i.e. about 5.2 hours after the GRB detection).  

The reduced spectrum is rather noisy and extends down to at least 3600 AA, indicating that the redshift is likely lower than z ~ 2. From preliminary reduction and calibration we tentatively infer a redshift of z ~ 1.39 from the possible detection of MgII 2796,2803. 
Further analysis is ongoing. 


GRB_name: GRB231104A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35008
SUBJECT: GRB 231104A: VZLUSAT-2 detection
DATE:    23/11/13 11:04:18 GMT
FROM:    Marianna DafÄÃ­kovÃ¡ at Masaryk University <500025@mail.muni.cz>

M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory),  N. Werner  (Masaryk U.), M. Ohno (Hiroshima U.),  L. Meszaros, B. Csak (Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory),  T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU)  -- the VZLUSAT-2/GRB payload collaboration.

The long-duration GRB 231104A (Fermi/GBM detection: GCN 34937; Fermi/LAT detection: GCN 34943; Swift/BAT detection: GCN 34938; AstroSat detection: GCN 34945; NuSTAR detection: GCN 34957; Konus/WIND trigger at 2023-11-04 01:47:39.141 UT, INTEGRAL/SPI-ACS peak detection at 2023-11-04 ~01:47:40 UT) was detected by the GRB detector on board of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).

The data acquisition was performed by the GRB detector unit no. 1. The detection was confirmed at the peak time 2023-11-04 01:47:39 UTC. The T90 duration is 26 s and the significance during T90 reaches 21 sigma.

The light curve obtained by VZLUSAT-2 is available here:
https://vzlusat2.konkoly.hu/static/share/GRB231104A_GCN_VZLUSAT2.pdf

All VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/
The GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral.


GRB_name: GRB231111A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35009
SUBJECT: GRB 231111A: Afterglow redshift from OSIRIS+/GTC
DATE:    23/11/13 11:53:53 GMT
FROM:    C. C. Thoene at ASU-CAS <christina.thoene@gmail.com>

C. C. Thoene (ASU-CAS), A. de Ugarte Postigo (CNRS/OCA), L. Izzo (INAF/Capodimonte), F. Agui Fernandez (CAHA), F. Perez Toledo (GTC), M. Blazek (CAHA), J. Fynbo (DAWN/NBI), S. Geier (GTC) and N.R. Tanvir (Univ. Leicester) report:

We observed the afterglow of GRB 231111A (Melandri et al. GCN 34981, Jiang et al. GCN 34982) with OSIRIS+ at the 10.4m GTC on Nov. 11, 2023, starting at 20:19:13 UT, 6h after the GRB. We obtained 3x900s exposures under bad seeing conditions (1.9 arcsec) using the R1000B grism, which gives a wavelength coverage between 3700 and 7800 A. At the time of observations, the afterglow had a magnitude of r~20.2 as determined from the acquisition image.

In the combined spectrum we detect the MgII 2796,2803 Ã… doublet and faint lines of FeII 2585 and 2600 Ã…, which results in a redshift of z=1.179. TNG (Dâ€™Avanzo et al. GCN 35007) also claims the detection of a MgII doublet, however, at their reported redshift of z=1.39, no lines are present in our spectrum. No fine-structure lines are detected, making the redshift of 1.179 strictly seen as a lower limit. However, given the lack of further emission or absorption features in the spectral range and the upper limit of z~2 due to the detection of continuum down to 3650 Ã… (similar to the claim of D'Avanzo et al. GCN 35007) we expect this to be the actual redshift of the GRB.

We acknowledge the excellent support by the GTC staff. 


GRB_name: GRB231110A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35011
SUBJECT: GRB 231110A: Swift-UVOT Upper Limits
DATE:    23/11/13 15:10:22 GMT
FROM:    N. Klingler at NASA-GSFC/UMBC/CRESST II <noelklingler@gmail.com>

Swift-UVOT has performed follow-up observations of the Swift-BAT-detected burst GRB 231110A (Kennea et al. GCN 34977), collecting 2.8 ks of observations between T0+8.80 ks and T0+27.45 ks.  No source was detected in the UVOT data at the position of the X-ray source reported by Evans et al. (GCN 34986).

3-sigma upper limits (AB) using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) are:

Filter      T_start(s)      T_stop(s)      Exp(s)       Mag
V   8893   9216    314.67 >19.55
B  14638  15545    881.77 >21.00
U  26828  27450    604.93 >21.67
W1  25992  26822    885.58 >21.76
white  15545  15695    147.43 >21.68

The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.198 in the direction of the burst (Schlegel et al. 1998).


GRB_name: GRB231111A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35012
SUBJECT: GRB 231111A: Xinglong-2.16m optical observations
DATE:    23/11/13 15:33:47 GMT
FROM:    Dong Xu at NAOC/CAS <dxu@nao.cas.cn>

S.Q. Jiang, Z.P. Zhu, S.Y. Fu, J. An, X. Liu, T.H. Lu, D. Xu (NAOC) report:

We observed the optical afterglow of GRB 231111A detected by Swift (Melandri et al., GCN 34981) using the 2.16m telescope
located at Xinglong, Hebei, China, equipped with the BFOSC camera. Observations started at 14:34:11 UT on 2023-11-11 (i.e., 16.87 min after the Swift/BAT trigger), and 3x200, 9x300 s frames were obtained in the R-band.

Preliminary photometric results of the optical afterglow (e.g., Melandri et al. GCN 34981; Jiang et al. GCN 34982; Lipunov et al. GCN 34983; Kumar et al. GCN 34984; Sun et al. GCN 34985; Pankov et al. GCN 34994; Ruocco et al. GCN 34997; Li et al. GCN 35001; Sun et al. GCN 35002; Moretti et al. GCN 35003; Komesh et al. GCN 35004) are as follows:

Tmid-T0 (day)  Filter     Magnitude (5-sigma)
   0.0153           R         17.89 +/- 0.01
   0.8523           R          >21.6

calibrated with the nearby Pan-STARRS field.

We thank the great support of the Xinglong-2.16m staff.


GRB_name: GRB231106A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35013
SUBJECT: GRB 231106A: Glowbug gamma-ray detection
DATE:    23/11/13 15:39:22 GMT
FROM:    C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>

C.C. Cheung, M. Kerr, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:

The Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 231106A, which was also detected by Fermi/GBM, CALET, and AstroSat/CZTI (GCN 34956, 34965, 34966).

Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-11-06 18:12:49.696. The light curve comprises an initial peak followed by a multi-peaked structure as observed by CALET (GCN 34965).

In the Glowbug data, the initial peak has a duration of 6.1 s and a total significance of about 24.1 sigma.  Using a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=0.4 and a cutoff energy ("Epeak") of 356 keV.  The modeled 10-10000 keV fluence is 1.9e-06 erg/cm^2.

The onset of the later multi-peaked structure observed by Glowbug is determined to be 2023-11-06 18:13:18.368 with a duration of 26.6 s and a total significance of about 46.1 sigma. Using a standard power-law function with an exponential high-energy cutoff to model the emission over this duration results in a photon index of x=2.0 and an Epeak of 204 keV.  The modeled 10-10000 keV fluence is 4.2e-06 erg/cm^2.

The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.

Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC.  It was launched on 2023 March 15 aboard the Department of Defense Space Test Programâ€™s STP-H9 to the ISS.  The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.

[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006

Distribution Statement A: Approved for public release.  Distribution is unlimited.


GRB_name: GRB231111A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35014
SUBJECT: GRB231111A: MDM 2.4m Hiltner Telescope Observation
DATE:    23/11/13 16:57:13 GMT
FROM:    Tianrui Sun at Purple Mountain Obs,CAS <trsun@pmo.ac.cn>


Tian-Rui Sun, Tian-Ci Zheng, Hui-Yang Mao, Jiang-Tao Li report:

Following the detection of GRB 231111A by SWIFT (Melandri et al., GCN 34981; Osborne et al., GCN 34991;GCN 34995), MASTER (Lipunov et al., GCN 34980; GCN 34983), Nanshan/HMT (Jiang et al., GCN 34982), GIT (Kumar et al., GCN 34984), YAHPT (Sun et al., GCN 34985), GECAM (Zhang et al., GCN 34990; GCN 34993), Mondy (Pankov et al., GCN 34994), Terskol Zeiss-2000 (Pankov et al., GCN 34996), Nastro Verde (Dainotti et al., GCN 34997), GMG (Mao et al., GCN 34999; GCN 35001), Mephisto (Sun et al., GCN 35002), Leavitt (Moretti et al., GCN 35003), NUTTelA-TAO (Komesh et al., GCN 35004) and Xinglong-2.16m (Jiang et al., GCN 35012), we conducted observations using the MDM 2.4m Hiltner telescope with the clear filter.

This observation began from 2023-11-12T01:44:16.415, about 11.4 hours after the burst.

The PSF photometry results are shown as :
----------------------------------------------------
UT                       exposure  filter mag        magerr
------------------------------------------------------
2023-11-12T01:44:16.415  600       Clear 20.7669 +/- 0.0622
2023-11-13T01:35:18.404  600       Clear 22.1815 +/- 0.0697
------------------------------------------------------


We used the GAIA-DR3 catalogue (G mag) as the magnitude reference for calibration.


GRB_name: GRB231110A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35015
SUBJECT: GRB 231110A: Swift-BAT refined analysis
DATE:    23/11/13 17:16:36 GMT
FROM:    Mike Moss at NASA GSFC <mikejmoss3@gmail.com>

S. Laha (GSFC/UMBC), S. D. Barthelmy (GSFC),
V. D'Elia (SSDC & INAF-OAR), H. A. Krimm (NSF), 
A. Y. Lien (U Tampa), C. B. Markwardt (GSFC),
M. J. Moss (GSFC), D. M. Palmer (LANL), 
T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),
M. Stamatikos (OSU) (i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 231110A (trigger #1195733)
(D'Elia, et al., GCN Circ. 34977).  The BAT ground-calculated position is
RA, Dec = 356.244, 82.630 deg which is 
   RA(J2000)  =  23h 44m 58.7s 
   Dec(J2000) = +82d 37' 48.6" 
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 34%.
 
The BAT light curve shows a single pulse structure with a duration of ~ 11 
seconds and peaking ~1.5 seconds after the trigger time.
T90 (15-350 keV) is 11.34 +- 1.56 sec (estimated error including systematics).
 
The time-averaged spectrum from T-1.60 to T+12.32 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.35 +- 0.11.  The fluence in the 15-150 keV band is 1.5 +- 0.1 x 10^-06 erg/cm2.
The 1-sec peak photon flux measured from T+0.63 sec in the 15-150 keV band
is 3.4 +- 0.4 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/1195733/BA/


GRB_name: GRB231110A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35020
SUBJECT: GRB 231110A: CALET Gamma-Ray Burst Monitor detection
DATE:    23/11/14 03:07:36 GMT
FROM:    Yuta Kawakubo at Louisiana State University <kawakubo1@lsu.edu>

S. Sugita, A. Yoshida, T. Sakamoto (AGU), Y. Kawakubo (LSU),
K. Yamaoka (Nagoya U), S. Nakahira (JAXA), Y. Asaoka (ICRR),
S. Torii, Y. Akaike, K. Kobayashi (Waseda U), Y. Shimizu, 
T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC),
M. L. Cherry (LSU), S. Ricciarini (U of Florence),
P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The long GRB 231110A (Swift detection: D'Elia et al., GCN Circ. 34977;
GECAM-B detection: Wang et al., GCN Circ. 34992; AstroSat CZTI 
detection: Navaneeth et al., GCN Circ. 35005; Glowbug gamma-ray 
detection: Cheung et al., GCN Circ. 35006; Swift-BAT refined analysis:
Laha et al., GCN Circ. 35015) triggered the CALET Gamma-ray Burst
Monitor (CGBM) at 21:19:35.19 UTC on 10 November 2023
(http://cgbm.calet.jp/cgbm_trigger/flight/1383686313/index.html).
The burst signal was seen by all CGBM detectors.  No real-time 
CGBM GCN notice was distributed about this trigger because
the real-time communication from the ISS was off (loss of signal).

The burst light curve shows a single pulse that starts
at T-1.0 sec, peaks at T+0.5 sec, and ends at T+1.5 sec.
The T90 and T50 durations measured by the SGM data are 2.1 +/- 0.2 sec
and 1.1 +/- 0.1 sec (40-1000 keV), respectively.

The ground-processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1383686313/index.html

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at Waseda University.


GRB_name: GRB231114A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35025
SUBJECT: GRB 231114A: Fermi GBM Final Localization
DATE:    23/11/14 13:16:58 GMT
FROM:    Andreas von Kienlin at MPE <azk@mpe.mpg.de>

The Fermi GBM team reports the detection of a likely SHORT GRB

"At 09:18:40.39 UT on 14 November 2023, the Fermi Gamma-ray Burst Monitor
(GBM)
triggered and located GRB 231114A (trigger 721646325/231114388).

The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 150.00, Dec = -36.55 (J2000 degrees, equivalent to J2000 10h 0m,
-36d 32'),
with a statistical uncertainty of 11.38 degrees.

The angle from the Fermi LAT boresight is 77 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231114388/quicklook/glg_skymap_all_bn231114388.png

The HEALPix FITS file, including the estimated localization systematic, can
be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231114388/quicklook/glg_healpix_all_bn231114388.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231114388/quicklook/glg_lc_medres34_bn231114388.gif"


GRB_name: GRB231114A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35028
SUBJECT: GRB 231114A (short): Glowbug gamma-ray detection
DATE:    23/11/14 19:47:23 GMT
FROM:    C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>

C.C. Cheung, M. Kerr, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:                                                                                                                                                                                                                                                   
 
The Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 231114A, which was also detected by Fermi/GBM (GCN 35025).
 
Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-11-14 09:18:39.280 with a duration of 0.256 s and a total significance of about 11.6 sigma.  The light curve comprises a single peak.
 
Using a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=-0.1 and a cutoff energy ("Epeak") of 421 keV.  The modeled 10-10000 keV fluence is 1.5e-07 erg/cm^2.
 
The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.
 
Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC.  It was launched on 2023 March 15 aboard the Department of Defense Space Test Programâ€™s STP-H9 to the ISS.  The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.
 
[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006
 
Distribution Statement A: Approved for public release.  Distribution is unlimited.


GRB_name: GRB231113A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35029
SUBJECT: GRB 231113A (short): Glowbug gamma-ray detection
DATE:    23/11/14 22:32:07 GMT
FROM:    C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>

C.C. Cheung, M. Kerr, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:
 
The Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of a short burst, GRB 231113A.
 
Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-11-13 17:57:11.152 with a duration of 1.02 s and a total significance of about 17.1 sigma.  The light curve comprises an initial, brighter peak at ~T0+0.4s and a secondary peak at ~T0+0.8s.
 
Using a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=0.2 and a cutoff energy ("Epeak") of 496 keV.  The modeled 10-10000 keV fluence is 5.8e-07 erg/cm^2.
 
The best-fit localization is RA, Decl. (J2000) = 153.5 deg, -65.4 deg with a radius of 24.7 deg (95% confidence), with a highly uncertain systematic uncertainty.
 
The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.
 
Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC.  It was launched on 2023 March 15 aboard the Department of Defense Space Test Programâ€™s STP-H9 to the ISS.  The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.
 
[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006
 
Distribution Statement A: Approved for public release.  Distribution is unlimited.


GRB_name: GRB231114A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35030
SUBJECT: Fermi GRB 231114A: Global MASTER-Net observations report
DATE:    23/11/14 22:47:08 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-SAAO robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 231114A ( Fermi GBM team, GCN 35025) errorbox  42669 sec after notice time and 42703 sec after trigger time at 2023-11-14 21:10:23 UT, with upper limit up to  18.1 mag. The observations began at zenith distance = 78 deg. The sun  altitude  is -36.8 deg. 

The galactic latitude b = 15 deg., longitude l = 269 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2305614

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

   42733 | 2023-11-14 21:10:23 |         MASTER-SAAO | (09h 16m 41.59s , -46d 56m 19.7s) |   C |    60 | 17.9 |        
   42812 | 2023-11-14 21:11:42 |         MASTER-SAAO | (09h 09m 16.66s , -45d 02m 40.0s) |   C |    60 | 17.5 |        
   42903 | 2023-11-14 21:13:13 |         MASTER-SAAO | (08h 58m 12.72s , -41d 14m 29.6s) |   C |    60 | 17.9 |        
   43074 | 2023-11-14 21:16:04 |         MASTER-SAAO | (09h 35m 43.50s , -48d 48m 37.4s) |   C |    60 | 17.6 |        
   43520 | 2023-11-14 21:23:30 |         MASTER-SAAO | (09h 13m 12.69s , -43d 08m 45.8s) |   C |    60 | 17.7 |        
   43770 | 2023-11-14 21:27:40 |         MASTER-SAAO | (09h 16m 41.55s , -46d 57m 23.9s) |   C |    60 | 18.0 |        
   43940 | 2023-11-14 21:30:30 |         MASTER-SAAO | (09h 20m 03.32s , -45d 01m 26.2s) |   C |    60 | 17.8 |        
   44020 | 2023-11-14 21:31:50 |         MASTER-SAAO | (08h 58m 13.04s , -41d 16m 17.4s) |   C |    60 | 18.0 |        
   44279 | 2023-11-14 21:36:09 |         MASTER-SAAO | (09h 35m 43.43s , -48d 48m 45.8s) |   C |    60 | 17.6 |        
   44452 | 2023-11-14 21:39:01 |         MASTER-SAAO | (09h 03m 44.32s , -43d 10m 07.9s) |   C |    60 | 17.9 |        
   44531 | 2023-11-14 21:40:21 |         MASTER-SAAO | (09h 13m 19.52s , -43d 09m 18.6s) |   C |    60 | 17.8 |        
   44622 | 2023-11-14 21:41:52 |         MASTER-SAAO | (09h 23m 46.90s , -43d 07m 57.2s) |   C |    60 | 17.5 |        
   44781 | 2023-11-14 21:44:31 |         MASTER-SAAO | (09h 16m 46.70s , -46d 55m 44.6s) |   C |    60 | 18.1 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB231111A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35033
SUBJECT: GRB 231111A: Swift-BAT refined analysis
DATE:    23/11/15 00:21:53 GMT
FROM:    Mike Moss at NASA GSFC <mikejmoss3@gmail.com>

A. Y. Lien (U Tampa), S. D. Barthelmy (GSFC),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
C. B. Markwardt (GSFC), A. Melandri (INAF-OAR),
M. J. Moss (GSFC), D. M. Palmer (LANL),
T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU),
M. Stamatikos (OSU) (i.e. the Swift-BAT team):

Using the data set from T-239 to T+200 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 231111A (trigger #1195887)
(Melandri, et al., GCN Circ. 34981).  The BAT ground-calculated position is
RA, Dec = 290.197, 52.440 deg which is
   RA(J2000)  =  19h 20m 47.3s
   Dec(J2000) = +52d 26' 22.9"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 61%.
 
The BAT light curve shows a FRED-pulse structure peaking ~0 seconds after the trigger time.
T90 (15-350 keV) is 34.08 +- 4.88 sec (estimated error including systematics).
 
The time-averaged spectrum from T-5.32 to T+40.06 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.58 +- 0.07.  The fluence in the 15-150 keV band is 3.4 +- 0.1 x 10^-06 erg/cm2.
The 1-sec peak photon flux measured from T+0.07 sec in the 15-150 keV band
is 2.7 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/1195887/BA/


GRB_name: GRB231115A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35035
SUBJECT: GRB 231115A: Fermi GBM Final Real-time Localization
DATE:    23/11/15 15:46:53 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely SHORT GRB

At 15:36:21 UT on 15 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231115A (trigger 721755386.20138 / 231115650).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 131.0, Dec = 73.5 (J2000 degrees, equivalent to J2000 08h 43m, 73d 30'), with a statistical uncertainty of 8.7 degrees.

The angle from the Fermi LAT boresight is 38.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231115650/quicklook/glg_skymap_all_bn231115650.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231115650/quicklook/glg_healpix_all_bn231115650.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231115650/quicklook/glg_lc_medres34_bn231115650.gif


GRB_name: GRB231115A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35036
SUBJECT: GRB 231115A position consistent with M 82 galaxy
DATE:    23/11/15 16:25:31 GMT
FROM:    Paolo D'Avanzo at INAF-OAB <pda.davanzo@gmail.com>

P. Dâ€™Avanzo (INAF - OAB), E. Palazzi (INAF - OAS), S. Campana (INAF - OAB), M. G. Bernardini (INAF - OAB), D. B. Malesani (DAWN/NBI & Radboud Univ.) 
on behalf of the CIBO collaboratio report:


GRB 231115A has been recently detected by Fermi/GBM (Fermi GBM team, GCN Circ. 35035) and INTEGRAL (https://gcn.gsfc.nasa.gov/other/10427.integral <https://gcn.gsfc.nasa.gov/other/10427.integral>). 

We note that the INTEGRAL position (which has an uncertainty radius or 3 arcmin) is consistent with the position of the M 82 galaxy (luminosity distance of ~ 3.5 Mpc). 

Follow-up observations are encouraged.  


GRB_name: GRB231115A
Detection_method: IBAS
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35037
SUBJECT: GRB 231115A: a short hard GRB detected by IBAS, poistionally coincident with M82
DATE:    23/11/15 16:26:24 GMT
FROM:    Diego Gotz at CEA <diego.gotz@cea.fr>

S.Mereghetti (INAF, IASF-Milano), D.Gotz (CEA, Saclay),   C.Ferrigno, E.Bozzo, V.Savchenko (ISDC, Versoix), L.Ducci (IAAT, Germany and ISDC, Versoix) and J.Borkowski (CAMK, Torun) report:

a short hard burst lasting about 150 ms has been detected by IBAS in the  IBIS/ISGRI data at 15:36:22  UT of November 15, 2023.

The refined coordinates (J2000) are:
R.A.= 149.000901 [degrees] 
DEC.=  69.680130  [degrees]
with an uncertainty of 2  arcmin (90% c.l.).

We note that this position is consistent with the galaxy M82, so this event, which also triggered Fermi/GBM,  may be due to a magnetar giant flare or to a nearby merger. So we encourage follow-up at other wavelengths.

A plot of the light curve will  be posted at 
http://ibas.iasf-milano.inaf.it/IBAS_Results.html


GRB_name: GRB231115A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35038
SUBJECT: GRB 231115A: significance of INTEGRAL localization alignment with M82
DATE:    23/11/15 17:29:21 GMT
FROM:    Eric Burns at LSU <erickayserburns@gmail.com>

Eric Burns (LSU)

INTEGRAL has localized the GRB 231115A to be coincident with the nearby, star-forming galaxy M82, suggesting a possible giant flare origin (S.Mereghetti et al., GCN 35037). Using the method in [1] we estimate the Bayes factor that this is a giant flare from M82 vs neutron star merger GRB with a chance alignment  to be approximately 180,000 to 1. The corresponding value for GRB 200415A, the previous most confident event is 6,000 to 1. The false alarm rate for GRB 231115A is beyond 4.5 sigma in Gaussian-equivalent significance. This is a lower bound as the necessary background simulations for more confident constraints will take weeks to run. We report this to support additional follow-up

We emphasize this is a very preliminary significance estimate, using code which had to be quickly modified and updated to handle Python package updates that occurred since it was last used, and it has not been checked carefully.

[1] E Burns et al., ApjL 907 2 2021


GRB_name: GRB231115A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35039
SUBJECT: Fermi GRB 231115A: Global MASTER-Net observations report
DATE:    23/11/15 17:30:44 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-Tunka robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB 231115A ( Fermi GBM team, GCN 35035) errorbox  4601 sec after notice time and 4635 sec after trigger time at 2023-11-15 16:53:37 UT, with upper limit up to  18.8 mag. The observations began at zenith distance = 47 deg. The sun  altitude  is -57.5 deg. 

The galactic latitude b = 34 deg., longitude l = 141 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2306520

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

    4726 | 2023-11-15 16:53:37 |        MASTER-Tunka | (09h 52m 05.00s , +66d 57m 09.9s) |   C |   180 | 14.1 |        
    4726 | 2023-11-15 16:53:37 |        MASTER-Tunka | (09h 53m 24.26s , +67d 39m 25.7s) |   C |   180 | 18.8 |        
    4890 | 2023-11-15 16:57:06 |        MASTER-Tunka | (09h 52m 11.37s , +66d 56m 35.9s) |   C |    90 | 15.5 |        
    4890 | 2023-11-15 16:57:06 |        MASTER-Tunka | (09h 53m 31.95s , +67d 38m 26.3s) |   C |    90 | 18.1 |        
    5007 | 2023-11-15 16:59:02 |        MASTER-Tunka | (09h 52m 07.51s , +66d 55m 13.1s) |   C |    90 | 13.3 |        
    5007 | 2023-11-15 16:59:03 |        MASTER-Tunka | (09h 53m 26.66s , +67d 37m 26.5s) |   C |    90 | 18.0 |        
    5124 | 2023-11-15 17:01:00 |        MASTER-Tunka | (09h 52m 12.62s , +66d 55m 43.4s) |   C |    90 | 15.3 |        
    5124 | 2023-11-15 17:01:00 |        MASTER-Tunka | (09h 53m 33.01s , +67d 37m 31.8s) |   C |    90 | 18.0 |        
    5242 | 2023-11-15 17:02:58 |        MASTER-Tunka | (09h 52m 11.14s , +66d 57m 23.6s) |   C |    90 | 15.4 |        
    5242 | 2023-11-15 17:02:58 |        MASTER-Tunka | (09h 53m 31.53s , +67d 39m 11.8s) |   C |    90 | 17.9 |        
    5356 | 2023-11-15 17:04:52 |        MASTER-Tunka | (09h 53m 32.24s , +67d 37m 28.1s) |   C |    90 | 17.6 |        
    5475 | 2023-11-15 17:06:50 |        MASTER-Tunka | (09h 52m 15.59s , +66d 57m 34.6s) |   C |    90 | 15.3 |        
    5475 | 2023-11-15 17:06:51 |        MASTER-Tunka | (09h 53m 35.65s , +67d 39m 20.1s) |   C |    90 | 17.6 |        
    5593 | 2023-11-15 17:08:49 |        MASTER-Tunka | (09h 52m 10.80s , +66d 56m 43.7s) |   C |    90 | 15.1 |        
    5593 | 2023-11-15 17:08:49 |        MASTER-Tunka | (09h 53m 30.64s , +67d 38m 28.1s) |   C |    90 | 17.7 |        
    5710 | 2023-11-15 17:10:46 |        MASTER-Tunka | (09h 52m 11.18s , +66d 57m 44.6s) |   C |    90 | 15.0 |        
    5710 | 2023-11-15 17:10:46 |        MASTER-Tunka | (09h 53m 30.87s , +67d 39m 28.0s) |   C |    90 | 17.6 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB231115A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35040
SUBJECT: GRB 231115A: Swift ToO observations
DATE:    23/11/15 18:06:33 GMT
FROM:    Phil Evans at U of Leicester <pae9@star.le.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a ToO observation of the INTEGRAL GRB 231115A. 
Automated analysis of the XRT data will be presented online at
https://www.swift.ac.uk/ToO_GRBs/00021625

Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. These are
not necessarily related to the INTEGRAL event. Any X-ray source
considered to be a probable afterglow candidate will be reported via a 
GCN Circular after manual consideration.

Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).

This circular is an official product of the Swift-XRT team.


GRB_name: GRB231115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35041
SUBJECT:  GRB 231115A: GROWTH-India discovery of a potential optical counterpart
DATE:    23/11/15 18:30:14 GMT
FROM:    Varun Bhalerao at IIT Bombay <varunb@iitb.ac.in>

R. Kumar, A. Salgundi, V. Swain, Y. Wagh, V. Bhalerao (IIT Bombay), G. C. Anupama, S. Barway (IIA), R. Norboo (IAO), T. Ahumada, V. Karambelkar, M. M. Kasliwal (Caltech) report on behalf of a larger collaboration

We observed the field of GRB 231115A (Fermi GBM Team, GCN 35035) with 0.7m GROWTH India telescope. We started observations at 2023-11-15 16:47:58.140 UT, 1.19 hours after the fermi trigger (as soon as the source became visible). We obtained multiple 300s exposures in multiple filters. We have multiple detections of a transient AT 2023xvj at RA = 09:56:00.2, Dec = 69:40:29.2, with r' = 19.2. Owing to the dense background, current total astrometric uncertainty is about 0.6". The source is 0.3' from the reported Integral position, consistent with their 2' uncertainty. The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction.

At this stage, we cannot rule out that this might be Nova or some other transient in M82. Further imaging and analysis is under way. We strongly encourage follow-up observations.

The GROWTH India Telescope (GIT, Kumar et al., 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/.


GRB_name: GRB231115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35043
SUBJECT: GRB 231115A: archival HST observations
DATE:    23/11/15 20:01:14 GMT
FROM:    Andrew Levan at Radboud University <a.levan@astro.ru.nl>

A.J. Levan (Radboud), B. Gompertz (Birmingham), D.B. Malesani (DAWN/NBI) report:

The field of GRB 231115A (Mereghetti et al. GCN 35037) has been previously observed on several occasions by the Hubble Space Telescope via targeted observations of M82. Visual inspection of the location of the suggested candidate identified by Kumar et al. (GCN 35041) indicates that the environment is unremarkable. In blue observations obtained in F435W (GO 10776, 29-03-2006), the source lies on the stellar field of the host galaxy, but no readily identifiable discrete sources can be seen (e.g. massive stars or star-forming regions). In the IR, the field resolves into a larger number of discrete sources, likely due to the smaller extinction. Several sources are present within the 0.6â€ error region in F110W observations (GO 11360, 01-01-2010) with magnitudes around F110W=22 (AB). However, the density of such sources at this location in the galaxy is such that none is an outstanding candidate to be physically associated with the optical transient identified by Kumar et al.

We note that this location is relatively remote from the bulk of M82 and is not obviously associated with substantial star-forming activity. Although not unprecedented, this would be a somewhat unusual location for a magnetar giant flare.


GRB_name: GRB231115A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35044
SUBJECT:  GRB 231115A:  Fermi Observations of a probable Magnetar Giant Flare from M82
DATE:    23/11/15 20:50:45 GMT
FROM:    Sarah Dalessi at UAH <sd0104@uah.edu>

S. Dalessi (UAH), O.J. Roberts (USRA/NASA-MSFC), P. Veres (UAH) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 15:36:21.20 UT on 15 November 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 231115A (trigger 721755386/231115650).
which was also detected by Integral (P. D'Avanzo et al. 2023, GCN 35036 and S.Mereghetti et al. 2023, GCN 35037).
The Fermi GBM Final Real-time Localization is reported in GCN 35035 and is consistent with the Integral position.

The angle from the Fermi LAT boresight is 38 degrees.

The GBM light curve single peak with a duration (T90)
of about 0.03 s (50-300 keV). The time-averaged spectrum
from T0-0.02 to T0+0.02 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is 0.5 +/- 0.2 and the cutoff energy,
parameterized as Epeak, is 580 +/- 60 keV.

The event fluence (10-1000 keV) in this time interval is
(6.3 +/- 0.4)E-07 erg/cm^2. The 64-ms peak photon flux measured
starting from T0+0.0 s in the 10-1000 keV band is 11 +/- 1 ph/s/cm^2.

Using the distance to M82 of 3.5 Mpc (P. D'Avanzo et al. 2023, GCN 35036), we derive an Eiso of 1.4e45 ergs and Liso of 1.9e46 erg s-1 (64 ms, 1-10,000 keV). This with the rise time of ~2 ms, hard spectral slope and soft-hard-soft spectral evolution of the event, are consistent with an MGF origin.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"


GRB_name: GRB231115A
Detection_method: IBAS
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35045
SUBJECT: GRB 231115A (short): Glowbug gamma-ray detection
DATE:    23/11/15 21:36:10 GMT
FROM:    C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>

C.C. Cheung, M. Kerr, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:                                                                                                                                                                                                                                                    

The Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of GRB 231115A, which was also detected by Fermi/GBM and IBAS, and found to be positionally consistent with M82 (GCN 35035, 35036, 35037, 35038, 35044).

Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-11-15 15:36:20.184 with a duration of 0.064 s and a total significance of about 23.3 sigma. The light curve comprises a single peak.

Using a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=1.0 and a cutoff energy ("Epeak") of 561 keV.  The modeled 10-10000 keV fluence is 4e-07 erg/cm^2.

The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.

Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC.  It was launched on 2023 March 15 aboard the Department of Defense Space Test Programâ€™s STP-H9 to the ISS.  The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.

[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006

Distribution Statement A: Approved for public release.  Distribution is unlimited.


GRB_name: GRB231115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35046
SUBJECT: GRB 231115A: MASTER optical observations
DATE:    23/11/15 21:39:48 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

P.Balanutsa (Lomonosov MSU), N.Budnev, O.Gress (ISU,API),A.Sankovich
V. Lipunov,  E. Gorbovskoy, N. Tiurina,
D.Vlasenko, Yu.Tselik, Ya.Kechin, A.Kuznetsov, K.Zhirkov,
A.Chasovnikov, I.Gorbunov, D.Zimnukhov, V.Senik, V.Topolev, D.Cheryasov,
A.Sosnovskij, V.Senik (Lomonosov Moscow State University, SAI, Physics
Department),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
D. Buckley (South African Astronomical Observatory),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico
FelixAguilar OAFA),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov (Blagoveschensk Educational State University)


MASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the  GRB 231115A (Fermi GBM Team GCN 35035, Mereghetti et al., GCN 35037)  errorbox 4607 sec after notice time and 4634 sec after trigger time at 2023-11-15 16:53:37 UT, with upper limit up to 21.3 mag.

Our first images (till T0+10669)  are ruined due to bad weather conditions.
Sinces T0+10669, during the observations the weather improved. The list of limits up to 21.3 is presented in the table below. In pictures with the maximum limit we do not see the source. In all our frames, the object GAIA 1070550388423847680 with a magnitude of 19.44, closest to the indicated area in (Kumar et al GCN 35041), is clearly visible.
The localization region of OT (Kumar et al GCN 35041) has a diffuse structure, but we definitely do not see a source there with a brightness of 19.5 or brighterat given position.
Despite the presence of images with  deeper upper limits, due to the diffuse structure of the galaxy in the localization region,
it is difficult to talk about weaker sources in the preliminary analysis.

We obtain a following upper limits.

Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

    4725 |        MASTER-Tunka |   C |   180 | 18.8 |
    5241 |        MASTER-Tunka |   C |    90 | 17.9 |
    5473 |        MASTER-Tunka |   C |    90 | 17.6 |
    5708 |        MASTER-Tunka |   C |    90 | 17.6 |
   10669 |        MASTER-Tunka |   C |   180 | 19.2 |
   10829 |        MASTER-Tunka |   C |    90 | 18.8 |
   11178 |        MASTER-Tunka |   C |    90 | 19.2 |
   11409 |        MASTER-Tunka |   C |    90 | 19.4 |
   11524 |        MASTER-Tunka |   C |    90 | 19.5 |
   11638 |        MASTER-Tunka |   C |    90 | 19.6 |
   11724 |        MASTER-Tunka |   C |    30 | 19.8 |
   11840 |        MASTER-Tunka |   C |    30 | 20.0 |
   11885 |        MASTER-Tunka |   C |   120 | 20.7 |  Coadd
   12230 |        MASTER-Tunka |   C |   810 | 21.1 |  Coadd
   11898 |        MASTER-Tunka |   C |    30 | 20.0 |
   11968 |        MASTER-Tunka |   C |    60 | 14.5 |
   11968 |        MASTER-Tunka |   C |    60 | 20.2 |
   12056 |        MASTER-Tunka |   C |    60 | 20.4 |
   12146 |        MASTER-Tunka |   C |   240 | 20.4 |  Coadd
   12158 |        MASTER-Tunka |   C |    90 | 19.9 |
   12273 |        MASTER-Tunka |   C |    90 | 19.9 |
   12399 |        MASTER-Tunka |   C |    90 | 20.0 |
   12489 |        MASTER-Tunka |   C |   270 | 20.4 |  Coadd
   12514 |        MASTER-Tunka |   C |    90 | 20.0 |
   12630 |        MASTER-Tunka |   C |    90 | 20.0 |
   12848 |        MASTER-Tunka |   C |    90 | 19.9 |
   13045 |        MASTER-Tunka |   C |    60 | 20.5 |
   13105 |        MASTER-Tunka |   C |   180 | 21.1 |  Coadd
   13285 |        MASTER-Tunka |   C |   540 | 21.0 |  Coadd
   13132 |        MASTER-Tunka |   C |    60 | 20.5 |
   13218 |        MASTER-Tunka |   C |    60 | 20.5 |
   13306 |        MASTER-Tunka |   C |    60 | 20.5 |
   13366 |        MASTER-Tunka |   C |   180 | 21.0 |  Coadd
   13391 |        MASTER-Tunka |   C |    60 | 20.5 |
   13478 |        MASTER-Tunka |   C |    60 | 20.5 |
   13564 |        MASTER-Tunka |   C |    60 | 20.5 |
   13624 |        MASTER-Tunka |   C |   180 | 21.1 |  Coadd
   13648 |        MASTER-Tunka |   C |    60 | 14.9 |
   13648 |        MASTER-Tunka |   C |    60 | 20.5 |
   13733 |        MASTER-Tunka |   C |    60 | 20.5 |
   13820 |        MASTER-Tunka |   C |    60 | 15.2 |
   13821 |        MASTER-Tunka |   C |    60 | 20.5 |
   13881 |        MASTER-Tunka |   C |   180 | 21.0 |  Coadd
   13907 |        MASTER-Tunka |   C |    60 | 20.5 |
   13993 |        MASTER-Tunka |   C |    60 | 20.5 |
   14095 |        MASTER-Tunka |   C |    90 | 19.9 |
   14201 |        MASTER-Tunka |   C |    60 | 20.5 |
   14261 |        MASTER-Tunka |   C |   180 | 21.2 |  Coadd
   14288 |        MASTER-Tunka |   C |    60 | 20.5 |
   14377 |        MASTER-Tunka |   C |    60 | 20.5 |
   14463 |        MASTER-Tunka |   C |    60 | 15.6 |
   14463 |        MASTER-Tunka |   C |    60 | 20.5 |
   14523 |        MASTER-Tunka |   C |   180 | 21.1 |  Coadd
   14548 |        MASTER-Tunka |   C |    60 | 20.5 |
   14633 |        MASTER-Tunka |   C |    60 | 20.5 |
   14717 |        MASTER-Tunka |   C |    60 | 15.5 |
   14718 |        MASTER-Tunka |   C |    60 | 20.5 |
   14778 |        MASTER-Tunka |   C |   180 | 21.2 |  Coadd
   14805 |        MASTER-Tunka |   C |    60 | 20.6 |
   14885 |        MASTER-Tunka |   C |    60 | 20.6 |
   14973 |        MASTER-Tunka |   C |    60 | 20.6 |
   15033 |        MASTER-Tunka |   C |   180 | 21.3 |  Coadd
   15060 |        MASTER-Tunka |   C |    60 | 15.4 |
   15061 |        MASTER-Tunka |   C |    60 | 20.6 |
   15147 |        MASTER-Tunka |   C |    60 | 20.6 |
   15233 |        MASTER-Tunka |   C |    60 | 15.6 |
   15233 |        MASTER-Tunka |   C |    60 | 20.5 |
   15293 |        MASTER-Tunka |   C |   180 | 21.1 |  Coadd
   15381 |        MASTER-Tunka |   C |   180 | 20.6 |
   15533 |        MASTER-Tunka |   C |    60 | 20.5 |
   15620 |        MASTER-Tunka |   C |    60 | 20.5 |
   15705 |        MASTER-Tunka |   C |    60 | 20.3 |
   15765 |        MASTER-Tunka |   C |   180 | 20.8 |  Coadd
   15796 |        MASTER-Tunka |   C |    60 | 20.3 |
   15885 |        MASTER-Tunka |   C |    60 | 20.4 |
   15966 |        MASTER-Tunka |   C |    60 | 20.4 |
   16051 |        MASTER-Tunka |   C |    60 | 14.6 |
   16051 |        MASTER-Tunka |   C |    60 | 20.3 |
Filter C is a clear (unfiltred) band.

Real time updated cover map and actual upper limits list available here:
https://master.sai.msu.ru/site/master2/observ.php?id=2306494

The observations began at zenith distance = 47 deg. The sun altitude is -57.5 deg. The galactic latitude b = 41 deg., longitude l = 141 deg.
The message may be cited.


GRB_name: GRB231106A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35047
SUBJECT: GRB 231106A: TESS identification of candidate optical counterpart
DATE:    23/11/15 22:20:46 GMT
FROM:    Rahul Jayaraman at MIT <rjayaram@mit.edu>

R. Jayaraman (MIT/MKI), R. Vanderspek (MIT/MKI), M.M. Fausnaugh (TTU), G. Mo (MIT/LIGO), and G.R. Ricker (MIT/MKI) report:

The Transiting Exoplanet Survey Satellite (TESS; Ricker et al. JATIS 1 2015) was observing 91% of the Fermi-GBM localization region for the gamma-ray burst GRB 231106A (GCN 34956). TESS observed this region at a 200 second cadence continuously from 1.5 days before the trigger to 6.4 days after the trigger. The GRB occurred during TESS observational Sector 71, and most of the GBM localization fell within Camera 4, CCD 1.

We inspected the full-frame image (FFI) from the publicly available TICA data archived at MAST (https://archive.stsci.edu/hlsp/tica) at the time of the Fermi trigger and identified a bright point source not present in previous TESS images. This point source is located at RA = 113.4482, Dec = 29.2245 (uncertainty 1-2"), which is 3.6Â° from the center of the Fermi-GBM error region, and is located within the 39.7% credible region of the Fermi sky map. We extracted a light curve for this source from the calibrated TESS FFIs produced by TICA (Fausnaugh et al. RNAAS 2020) using difference imaging and forced photometry. Our analysis procedure is described in Fausnaugh et al. 2023 (ApJ 956(2):108).

TESS observations show that this optical transient rises rapidly (in less than 200 seconds), peaks at a magnitude of 13.8 in the TESS band (600 nmâ€“1000 nm), and then decays to the detection limit within 2000 seconds, with a power-law index of -0.95 Â± 0.28. The 3-sigma detection limit around the time of the trigger was 17.5.

This circular includes data collected with the TESS mission, obtained from the MAST data archive at the Space Telescope Science Institute (STScI). Funding for the TESS mission is provided by the NASA Explorer Program. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5â€“26555.


GRB_name: GRB231115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35048
SUBJECT: GRB 231115A: pre-burst ZTF upper limits for GRB optical counterpart candidate 
DATE:    23/11/15 22:21:51 GMT
FROM:    Tomas Ahumada Mena at Caltech <tahumada@caltech.edu>

Tomas Ahumada (CIT), Jacob Wise (LJMU), Michael Coughlin (UMN), on behalf of the ZTF and GROWTH collaboration: 

We serendipitously observed the localization region of GRB 231115A (GCN 35035) as part of routine Zwicky Transient Facility (ZTF; Graham et al., 2019; Bellm et al., 2019) survey operations. We most recently obtained images in the g-, and r-bands beginning ~1.2 days before the trigger time.  We report recent upper limits for the GRB optical counterpart candidate AT 2023xvj/GIT231115aa (GCN 35041) in the table below: 

Filter | mjd | mag lim (AB mag)
----------------------
r  | 60262.4944329 | 20.47
g | 60262.4463542 | 20.37

Additionally, we ran forced photometry on ZTF images (Masci et al. 2019) at the location of the transient, and found no previous activity at the 4 sigma level since the beginning of the ZTF survey (March 2018).

We note the latest ATLAS (Tonry et al. 2018, Smith et al. 2020) observations of the field were 7 days prior to the burst, reaching a limit of 19.2 mag in the r-band.



ZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA; WIS, Israel; OKC, Sweden; JSI/UMd, USA; U Washington, USA; DESY, Germany; MOST, Taiwan; UW Milwaukee, USA; LANL USA; Tokyo Tech, Japan; IITB, India; IIA, India; LJMU, UK; TTU, USA; SDSU, USA and USyd, Australia. ZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341. GROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949. Alert distribution service provided by DIRAC@UW (Patterson et al. 2019). Alert database searches are done by AMPEL (Nordin et al. 2019) and Kowalski (Duev et al. 2019). GROWTH India telescope is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA). GROWTH-India project is supported by SERB and administered by IUSSTF, under grant number IUSSTF/PIRE Program/GROWTH/2015-16 and IUCAA. Fritz and SkyPortal acknowledge the generous support of The Gordon and Betty Moore Foundation, through the Data-Driven Investigator Program.


GRB_name: GRB231115A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35049
SUBJECT: GRB 231115A: Non-detection in low-latency of gravitational waves with LIGO/Virgo/KAGRA
DATE:    23/11/15 22:24:45 GMT
FROM:    brina.martinez@ligo.org

The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report:

At the time of GRB 231115A, the LIGO Hanford Observatory (H1) was observing with a binary neutron star (BNS) merger average sensitive range of ~150 Mpc. The low-latency pipelines for compact binary mergers [1-4] were operational at the time of the GRB. No gravitational-wave candidates were found in a window of [-5, +1] seconds around GRB 231115A [5]. We find that H1 was sensitive to gravitational waves from both Fermi (GCN 35035) and INTEGRAL (GCN 35036, 35037) sky positions. An offline analysis will be performed to search for extremely weak gravitational-wave signals and determine exclusion limits.

[1] Tsukada et al. PRD 108, 043004 (2023) and Ewing et al. arXiv:2305.05625 (2023)
[2] Aubin et al. CQG 38, 095004 (2021)
[3] Dal Canton et al. ApJ 923, 254 (2021)
[4] Chu et al. PRD 105, 024023 (2022)
[5] Urban, A. L. 2016, Ph.D. Thesis https://dc.uwm.edu/etd/1218 and Piotrzkowski, B. J. 2022, Ph.D. Thesis https://dc.uwm.edu/etd/3060 


GRB_name: GRB231115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35050
SUBJECT: GRB 231115A: GOTO pre-burst limits of AT2023xvj
DATE:    23/11/15 22:41:25 GMT
FROM:    kendall.ackley@warwick.ac.uk

K. Ackley, D. Steeghs, B. P. Gompertz, A. J. Levan, D. B. Malesani, R. Starling, M. J. Dyer, J. Lyman, K. Ulaczyk, F. Jimenez-Ibarra, A. Kumar, D. O'Neill, D. K. Galloway, V. Dhillon, P. O'Brien; G. Ramsay, K. Noysena, R. Kotak, R. P. Breton, L. K. Nuttall, E. Pall'e and D. Pollacco report on behalf of the GOTO collaboration:

The Gravitational-wave Optical Transient Observer (GOTO; Steeghs et al. 2022) serendipitously covered the field of GRB 231115A (Fermi GBM Team, GCN 35035; Mereghetti et al, GCN 35037; Cheung et al. GCN 35045) at 04:44:17 UT on 2023-11-15. This is 10.87 hours before trigger and 16.9 hours later than the limits reported in Ahumada et al. (GCN 25048). The observation consisted of a 12x60s exposure set in the GOTO L-band (400-700 nm).

Analysis at the location of the potential optical transient https://www.wis-tns.org/object/2023xvj (Kumar et al. GCN 35041) does not show evidence of the source to a 3-sigma limiting AB magnitude of L > 20.1.

Images were processed immediately after acquisition using the GOTO pipeline. Difference imaging was performed manually on the stacked set using recent survey observations of the same pointings. 

Magnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and are not corrected for Galactic extinction.

Further observations are scheduled during the coming nights.

GOTO (https://goto-observatory.org) is a network of telescopes that is principally funded by the STFC and operated at the Roque de los Muchachos Observatory on La Palma, Spain, and Siding Spring Observatory in NSW, Australia, on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory & Planetarium, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT), the University of Turku, the University of Portsmouth, the University of Manchester and the Instituto de Astrofisica de Canarias (IAC).


GRB_name: GRB231115A
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35051
SUBJECT: GRB231115A: GRANDMA Observations
DATE:    23/11/15 23:22:01 GMT
FROM:    Cristina Andrade at UMN <andra104@umn.edu>

A. Iskandar (XAO), F. Wang (THU/BJP), J. Zhu (BJP), L. Wang, X. Zeng, C. Andrade (UMN), A. de Ugarte Postigo (CNRS/OCA), D. Akl (AUS), E. Broens (KNC), S. Antier (OCA-Artemis), I. Tosta e Melo (UniCT-DFA), P. Hello (IJCLAB), D. Turpin (CEA-Saclay/Irfu), T. Pradier (Unistra/IPHC), M. Coughlin (UMN), S. Karpov (FZU), J. Peloton (IJCLab) report on behalf of the GRANDMA collaboration:

We observed the field of GRB 231115A (Fermi GBM team, GCN 35035) covering the complete INTEGRAL error box (Dâ€™Avanzo et al. GCN 35036;Mereghetti et al. GCN 35037) within the GRANDMA collaboration. Imaging with the 0.4m SNOVA telescope did not find any candidate in r-band around 2023-11-15 17:37:53 (e.g 2h after the trigger time) down to an upper limit of 18.9 (5-sigma threshold) or 19.3 (3-sigma threshold) using PS1 catalog as photometric comparison. We also looked carefully at the location of AT 2023xvj (Kumar et al. GCN 35041).

The amateur contribution to GRANDMA, Kilonova Catcher (KNC), made no detection with a 30x180s image using a clear filter on 2023-11-15T20:00 UTC (TGRB + 3.28h). We determine a detection limit of 20 mag in r-band, using PS1 for calibration and color term correction. At 2023-11-15T18:53:25.219, we obtained R>18 from 5x180s exposure. The upper limit is given at 5-sigma averaged over all the images.

These upper limits are consistent with previous reports by MASTER (Lipunov et al. GCN 35046).

GRANDMA is a worldwide telescope network (grandma.ijclab.in2p3.fr) devoted to the observation of transients in the context of multi-messenger astrophysics (Antier et al. 2020 MNRAS 497, 5518). Kilonova-Catcher (KNC) is the citizen science program of GRANDMA (http://kilonovacatcher.in2p3.fr/).


GRB_name: GRB231115A
Detection_method: IBAS
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35052
SUBJECT: GRB 231115A: Kinder observations with Lulin observatory
DATE:    23/11/16 00:01:49 GMT
FROM:    Ting-Wan Chen at MPE <janet.chen@astro.su.se>

T.-W. Chen, C.-S. Lin (both NCUIA), A.J. Levan (Radboud), S. Schulze (CIERA, NW), M. Fraser (UCD), P. D'Avanzo (INAF - OAB), J. Lyman (Warwick), Y.-C. Cheng, C.-H. Wang (both NTNU), S. Yang (HNAS), M.-H. Lee, Y.-C. Pan, C.-C. Ngeow, H.-Y. Hsiao, W.-J. Hou, J.-K. Guo (all NCUIA), M. Fulton, S. Srivastav, T. Moore, C. Angus, A. Aamer (all QUB) and S. Smartt (Oxford/QUB) report:

We observed the field of GRB 231115A, a short GRB discovered by the Fermi GBM (Fermi GBM Team, GCN 35035). The GRB position is consistent with M 82 galaxy (Dâ€™Avanzo et al., GCN 35036). This burst is also detected by IBAS (Mereghetti et al., GCN 35037), INTEGRAL (Burns, GCN 35038) and Glowbug on the ISS (Cheung et al., GCN 35045). The GROWTH-India discovery of a potential optical counterpart AT 2023xvj with r~19.2 (Kumar et al., GCN 35041), taken on 1.19 hours after the Fermi trigger.

We used the 40cm SLT at Lulin Observatory, Taiwan to obtain r, i and z-band images of the field of M82, as part of the Kinder collaboration (Chen et al., AstroNote 2021-92).
The first SLT epoch of observations started at 16:46 UT on 15 of November 2023 (MJD = 60263.699), 1.15 hours after the Fermi GBM trigger. The images were combined from 7 frames with a 300-second exposure time for the r band, taken under seeing conditions of an average of 1.6" and at a median airmass of 2.14. We then took i-band images for 15 frames started at 18:56 UT, each with 300-second exposure time, taken under seeing conditions of an average of 2.2" and at a median airmass of 1.58. Finally, starting at 20:10 UT we observed z-band images for 13 frames, each with 300-second exposure time, taken under seeing conditions of an average of 2.0" and at a median airmass of 1.49.

We used the Kinder pipeline (Yang et al. A&A 646, A22) to measure the 3-sigma limits on the source location. We obtained the following preliminary magnitudes (in the AB system):

r > 19.23 mag,
i > 19.48 mag and,
z > 18.53 mag.

The given limit is derived based on calibrating against Pan-STARRS1 field stars and is not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V) = 0.14 mag in the direction of the burst (Schlafly & Finkbeiner 2011).

We do not see the source AT 2023xvj in the combined r, i and z-band images, nor in a subtraction against images obtained from the Legacy survey. However, the relatively poor conditions combined with high underlying surface brightness from the galaxy substantially reduce our sensitivity, and we would at best have marginally detected the transient identified by Kumar et al. (GCN 35041).


GRB_name: GRB231115A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35053
SUBJECT: GRB 231115A: Upper limits from a neutrino search with IceCube
DATE:    23/11/16 02:50:50 GMT
FROM:    Sam Hori at IceCube/U Wisc-Madison <sahori@wisc.edu>

The IceCube Collaboration (http://icecube.wisc.edu/) reports:



IceCube has performed a search for track-like muon neutrino events arriving from the direction of GRB 231115A (GCN Circ. 35035<https://gcn.nasa.gov/circulars/35035> (Fermi-GBM), INTEGRAL GCN Notice 10427<https://gcn.gsfc.nasa.gov/other/10427.integral>), a likely magnetar giant flare in M82 (D'Avanzo et al., GCN Circ. 35036<https://gcn.nasa.gov/circulars/35036>; Mereghetti et al., GCN Circ 35037<https://gcn.nasa.gov/circulars/35037>; Burns, GCN Circ 35038<https://gcn.nasa.gov/circulars/35038>).


We searched a time window off +/- 2000 seconds from the initial trigger reported by INTEGRAL (23/11/15 15:36:22.88 UT), during which IceCube was collecting good quality data. We used the offline direction reported by INTEGRAL (INTEGRAL GCN Notice 10427<https://gcn.gsfc.nasa.gov/other/10427.integral>).  Zero track-like events are found in coincidence with the position of the GRB. We accordingly derive a time-integrated muon-neutrino flux upper limit for this source of E^2 dN/ dE = 7.6*10^-2 GeV cm^-2 at 90% CL, under the assumption of an E^-2 power-law spectrum. 90% of events IceCube would detect from a source at this declination with an E^-2 spectrum have energies in the approximate energy range between 500 GeV and 130 TeV.


The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu<mailto:roc@icecube.wisc.edu>.


[1] IceCube Collaboration, R. Abbasi  et al., ApJ 910 4 (2021)


GRB_name: GRB231115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35054
SUBJECT: GRB 231115A: archival Chandra X-ray observations
DATE:    23/11/16 05:14:29 GMT
FROM:    Albert Kong at NTHU <akhkong@gmail.com>

A.K.H. Kong (NTHU), K.-L. Li (NCKU) report:

Following the discovery of GRB 231115A (GCN 35035) in the direction of M82 and its optical counterpart candidate AT 2023xvj (GCN 35041), we searched for X-ray emission from the progenitor with the Chandra X-ray Observatory. Chandra observed M82 with the ACIS detector 32 times between 2000 and 2016, with a total exposure time of about 561 ks. We combined all the observations and no source is visible at the position of the optical transient. We derive a 3-sigma luminosity limit of 2.3e37 erg/s (0.3-10 keV; D=3.5 Mpc) by assuming an absorbed power-law model with a photon index of 2. 


GRB_name: GRB231115A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35055
SUBJECT: GRB 231115A / AT2023xvj: Updated GIT analysis
DATE:    23/11/16 06:07:34 GMT
FROM:    Varun Bhalerao at IIT Bombay <varunb@iitb.ac.in>

R. Kumar (IIT Bombay), V. Karambelkar (Caltech), V. Swain, V. Bhalerao, A. Salgundi, Y. Wagh (IIT Bombay), G. C. Anupama, S. Barway (IIA), R. Norboo (IAO), T. Ahumada, M. M. Kasliwal (Caltech) report on behalf of a larger collaboration

We undertook refined analysis of GIT231115AA / AT2023xvj (Kumar et al, GCN 35041). The source is detected in 25 individual r-band images obtained by GIT (https://sites.google.com/view/growthindia/results/at2023xvj), as well as in a stacked image.

We investigated the reference images from PanSTARRS used for image subtraction and find a small, fuzzy, "negative" artifact at the location of the source (see link above), which may boost the counts at the source location. This had been considered in the original report, and excluded due to three reasons: first, the measured source flux is varying despite fixed exposure times, which makes it unlikely that they are all caused due to the same artifact. Second, there are similar artifacts at other locations in the reference images which do not create such bright spurious sources. Third, the source shows a PSF-like profile while the reference image artifact does not.

Other groups have reported non-detections which are broadly consistent with our detection: Balanutsa et al, (GCN 35046) report an upper limit of 21.3 which is comparable to our image sensitivity of 21.45 (5-sigma). However, the candidate is in a high background region which will result in shallower upper limits. Upper limits reported by Iskandar et al (GCN 35051 - 18.9 mag), and Chen et al (GCN 35052 - 19.2 mag) are consistent with our measurement.

Given the complex nature of background in the M82 field and the potential artifact, we undertook manual image subtraction using SDSS images as a reference. In this scenario, the subtraction is noisier, and we do not detect any source at the location of GIT231115AA / AT2023xvj, to a limiting magnitude of 19.3 (5-sigma).

Given this analysis, we caution observers that AT2023xvj be treated as a candidate, not a secure counterpart.


GRB_name: GRB231115A
Detection_method: IBAS
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35056
SUBJECT: GRB 231115A: Gaoyazi/GOT follow-up and archival observations
DATE:    23/11/16 06:31:54 GMT
FROM:    Dong Xu at NAOC/CAS <dxu@nao.cas.cn>

S.Q. Jiang, X. Liu, S.Y. Fu, J. An, Z.P. Zhu, T.H. Lu, D. Xu (NAOC), L.F. Huo, S.W. Luo, M.M. Yang, Z. K. Feng (GYZO) report:

We observed the field of GRB 231115A, a short GRB detected by the Fermi GBM (Fermi GBM Team, GCN 35035), INTEGRAL (Mereghetti et al., GCN 35037), and Glowbug (Cheung et al., GCN 35045), using the GOT-0.5m telescope located at Gaoyazi, Xinjiang, China. Observations started at 16:36:59 UT on 2023-11-15, i.e., 1.01 hr after the Fermi/GBM trigger, and we obtained 40x60 s frames in the Sloan r-filter and 40x90 s frames in the Sloan z-filter.

No credible optical transient is detected in our stacked images within and beside the error region of the INTEGRAL by the means of catalogue cross-match and image subtraction, down to 3-sigma limiting magnitudes of r>20.1 @ 1.38 hr and z>18.0 @ 2.86 hr post-burst, calibrated with nearby PanSTARRS stars. The magnitude is not corrected for Galactic extinction.

The field is also covered by the GW survey program at the GOT. The latest template was taken on 2023-10-05 and it gives upper limit down to r>18.8 within the  INTEGRAL/IBAS error region.


GRB_name: GRB231115A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35057
SUBJECT: GRB 231115A : MITSuME Akeno and Okayama optical upper limits
DATE:    23/11/16 08:39:17 GMT
FROM:    hayatsu@hp.phys.titech.ac.jp

S. Hayatsu, N. Higuchi, I. Takahashi, M. Sasada (Tokyo Tech), K. L. Murata (Kyoto U),  
M. Niwano, S. Sato, H. Seki, H. Takei, Y. Yatsu and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration:

We observed a field of GRB 231115A ( Fermi GBM Team GCN Circular #35035) with optical three-color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescopes Akeno and Okayama. 

The observation started at 2023-11-15 17:17:29 UT (6068 seconds after the Fermi/GBM trigger). We stacked the images with good conditions. We did not detect any obvious point sources at the position reported by Kumar et al. GCN Circular #35041. We obtained the 5-sigma limits of the stacked images as follows.

T0+[sec] | MID-UT | T-EXP[sec] | 5-sigma limits
------------------------------------------------------------------------------------------------
# MITSuME Akeno
6482 | 2023-11-15 17:24:23 | 600.0 | g'>19.6, Rc>19.5, Ic>19.0
7527 | 2023-11-15 17:41:48 | 1200.0 | g'>20.0, Rc>19.8, Ic>19.3
9612 | 2023-11-15 18:16:33 | 2400.0 | g'>20.4, Rc>20.2, Ic>19.7
# MITSuME Okayama
12526 | 2023-11-15 19:05:07 | 7380.0 | g'>19.1, Rc>19.9, Ic>19.2
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time

We used the PS1 catalog for flux calibration. The catalog magnitudes in PS1 g, r and i bands were converted to our g', Rc and Ic band magnitudes following Tonry et al. (2012), Table 6. The magnitudes are expressed in the AB system. The images were processed in real-time through the MITSuME GPU reduction pipeline (Niwano et al. 2021, PASJ, Vol.73, Issue 1, Pages 4-24; https://github.com/MNiwano/Eclaire).


GRB_name: GRB231116A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35058
SUBJECT: GRB 231116A: Fermi GBM Final Real-time Localization
DATE:    23/11/16 09:51:03 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 09:40:34 UT on 16 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231116A (trigger 721820439.761364 / 231116403).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 24.6, Dec = -36.8 (J2000 degrees, equivalent to J2000 01h 38m, -36d 47'), with a statistical uncertainty of 11.2 degrees.

The angle from the Fermi LAT boresight is 23.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231116403/quicklook/glg_skymap_all_bn231116403.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231116403/quicklook/glg_healpix_all_bn231116403.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231116403/quicklook/glg_lc_medres34_bn231116403.gif


GRB_name: GRB231115A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35059
SUBJECT: GRB 231115A: GBM/Fermi Observations of a probable Giant Flare of Magnetar
DATE:    23/11/16 09:52:35 GMT
FROM:    Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>

P. Minaev (IKI), A. Pozanenko (IKI) report on behalf of GRB IKI FuN:

We analyzed GRB 231115A, detected till now by GBM/Fermi (GCN 35035, GCN 35044) and INTEGRAL (GCN 35037), Glowbug (GCN 35045), using publicly available data of GBM/Fermi. The light curve of the burst is FRED-like with duration of T_90 = 0.06 +/- 0.01 s in (7, 850) keV energy range. The spectral analysis in a time interval of (-0.05, 0.05) s since GBM trigger, the best fit is obtained for CPL model with following parameters: E_p = 613 (- 60, +74) keV, alpha = 0.33 +/- 0.21. The fluence of F = (7.2 +/- 0.5)E-7 erg/cm**2 is obtained in 10 - 1000 keV energy band, Eiso = (1.24 +/- 0.14)E45 erg in (1, 10000) keV energy range for D_L = 3.5 Mpc of M82. Using Ep,i â€“ Eiso correlation and T_90,i - EH diagram [1,2] we classify the burst as the SGR giant flare. Taking into account the non-detection of gravitational waves with LIGO/Virgo/KAGRA (LIGO Scientific Collaboration, Virgo Collaboration, KAGRA Collaboration, GCN 35049) we can suggest the GRB 231115A as the giant flash of a new SG!
 R in M82 galaxy.

Ep,i â€“ Eiso correlation can be found at http://grb.rssi.ru/GRB231115A/GRB231115A_Ep-Eiso.png

T_90,i - EH diagram can be found at http://grb.rssi.ru/GRB231115A/GRB231115A_EHD.png

[1] - Minaev et al., MNRAS, 492, 1919, 2020 
[2] - Minaev et al., Astronomy Letters, 46, 9, 573, 2020


GRB_name: GRB231115A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35060
SUBJECT: GRB 231115A: Insight-HXMT/HE detection
DATE:    23/11/16 11:03:52 GMT
FROM:    Kai Kai <wcxuemail@gmail.com>

W. C. Xue, S. L. Xiong, X. B. Li and C. K. Li
report on behalf of the Insight-HXMT team:

At 2023-11-15T15:36:21.200 (T0), Insight-HXMT/HE detected
GRB 231115A (trigger ID: HEB231115650) in a routine search of the data,
which was also observed by Fermi/GBM (Fermi GBM Team, GCN 35035 & 35044),
INTEGRAL (P. D'Avanzo et al., GCN 35036, S. Mereghetti et al. GCN 35037)
and Glowbug (C. C. Cheung et al., GCN 35045). This burst is probably a
giant flare from a magnetar in the nearby galaxy M82.

The Insight-HXMT/HE light curve mainly consists of single
pulse with a duration (T90) of 0.08 s measured from T0-0.01 s.
The 1-ms peak rate, measured from T0-0.01 s, is 16611 cnts/sec.
The total counts from this burst is 210 counts.
URL_LC: https://twikinew.ihep.ac.cn/pubhxmt/HXMT/GRBList/HEB231115650_lc.jpg

All measurements above are made with the CsI detectors operating in the
regular mode with the energy range of about 80-800 keV (deposited energy).
Only gamma-rays with energy greater than about 200 keV can penetrate
the spacecraft and leave signals in the CsI detectors installed inside
the telescope.

Insight-HXMT is the first Chinese space X-ray telescope, which was
funded jointly by the China National Space Administration (CNSA) and
the Chinese Academy of Sciences (CAS).
More information about it could be found at:
http://www.hxmt.org.


GRB_name: GRB231115A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35061
SUBJECT: GRB 231115A: AGILE/MCAL upper limits
DATE:    23/11/16 11:53:27 GMT
FROM:    Francesco Verrecchia at SSDC,INAF-OAR <francesco.verrecchia@ssdc.asi.it>

C. Pittori, F. Verrecchia (SSDC, and INAF/OAR), M. Tavani (INAF/IAPS,
and Univ. Roma Tor Vergata), C. Casentini, L. Foffano (INAF/IAPS),
G. Piano (INAF/IAPS), A. Ursi (ASI and INAF/IAPS), L. Baroncelli,
A. Bulgarelli, A. Ciabattoni, A. Di Piano, V. Fioretti, G. Panebianco,
N. Parmiggiani (INAF/OAS-Bologna), M. Pilia (INAF/OA-Cagliari),
P.W. Cattaneo (INFN Pavia), F. Cutrona (Univ. Milano Bicocca),
F. Longo (Univ. Trieste, and INFN Trieste), report on behalf
of the AGILE Team:

AGILE observed the short GRB 231115A first reported by Fermi GBM at
T0 = 15:36:21 UT on 15 Nov 2023 (GCN #35035) and significantly localized
by INTEGRAL in M82 (GCN #35036, #35037, #35038), suggesting a possible
magnetar giant flare origin (also GCN #35044).

The GRB location was fully accessible to the AGILE MCAL at about 70
degrees off-axis, but no trigger occured around +/- 50 sec from T0.

The three-sigma upper limit (UL) obtained for a 1 s integration time
at  the GRB position is 1.3E-06 erg cm^-2 (assuming as spectral model a
single power law with photon index 1.5).


The AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive
in the energy range 0.4-100 MeV. Additional analysis of AGILE data
is in progress.


GRB_name: GRB231115A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35062
SUBJECT: Konus-Wind detection of GRB 231115A (a probable Magnetar Giant Flare from M82)
DATE:    23/11/16 12:43:51 GMT
FROM:    Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>

D. Frederiks, D. Svinkin, A.Lysenko, A. Ridnaia,
Yu. Temiraev, A. Tsvetkova,  M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:

The short duration, hard spectrum GRB 231115A
(Fermi GBM detection: Fermi GBM team GCN 35035, Dalessi et al. GCN 35044;
INTEGRAL (IBAS) detection: Mereghetti et al., GCN 35037;
Glowbug detection: Cheung et al., GCN 35045)
triggered Konus-Wind (KW) at T0= 56183.509 s UT (15:36:23.509).

The burst light curve shows a single FRED-like pulse,
which starts, at ~T0-0.028 s with the fast (<4 ms) rise of
the emission intensity, which peaks at ~T0-0.016 s
and has a total duration of ~66 ms.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB231115_T56183/

As observed by Konus-Wind, the burst had
a fluence of (7.3 Â± 0.1)x10^-7 erg/cm^2 and
a 16-ms peak energy flux, measured from T0 - 0.018 s,
of (2.2 Â± 0.45)x10^-5 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum (measured from T0-0.028 s to T0+0.036 s)
is best fit in the 20 keV - 1.5 MeV range by a power law with exponential
cutoff (CPL) model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = 0.69(-0.54,+0.96) and Ep = 495(-77,+118) keV.
A blackbody (BB) spectral model fits the spectrum equally well,
with the BB temperature kT = 114(-10,+9) keV.

Assuming the likely GRB 231115A association with the nearby
M82 galaxy at ~3.5 Mpc (Dâ€™Avanzo et al., GCN 35036;
Mereghetti et al., GCN 35037; Burns GCN 35038),
we estimate the burst isotropic energy Eiso to ~1.1x10^45 erg and
the 16-ms peak luminosity Liso to ~3.2x10^46 erg/s.
These values are in the range the of the energetics of initial pulses
of magnetar giant flares (MGFs), which, assuming the short rise time
and the hard energy spectrum of the burst, supports its MGF origin.

At 3.5 Mpc, the characteristic radius of the emission region,
estimated from the KW blackbody spectral fit, is R~30 km,
the same order of magnitude as the radius of a neutron star or its magnetosphere.

All the quoted errors are estimated at the 68% confidence level.
All the presented results are preliminary.


GRB_name: GRB231116A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35063
SUBJECT: Fermi GRB 231116A: Global MASTER-Net observations report
DATE:    23/11/16 14:31:28 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-Tunka robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB 231116A ( Fermi GBM team, GCN 35058) errorbox  11646 sec after notice time and 11682 sec after trigger time at 2023-11-16 12:55:17 UT, with upper limit up to  17.5 mag. The observations began at zenith distance = 79 deg. The sun  altitude  is -33.8 deg. 

The galactic latitude b = -76 deg., longitude l = 258 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2307066

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

   11712 | 2023-11-16 12:55:17 |        MASTER-Tunka | (01h 20m 09.29s , -24d 19m 42.3s) |   C |    60 | 13.3 |        
   12543 | 2023-11-16 13:09:07 |        MASTER-Tunka | (01h 37m 31.14s , -23d 35m 46.0s) |   C |    60 | 13.5 |        
   14164 | 2023-11-16 13:36:08 |        MASTER-Tunka | (01h 38m 09.70s , -26d 14m 15.0s) |   C |    60 | 15.0 |        
   14164 | 2023-11-16 13:36:09 |        MASTER-Tunka | (01h 39m 04.83s , -25d 30m 31.7s) |   C |    60 | 17.5 |        
   15153 | 2023-11-16 13:52:38 |        MASTER-Tunka | (01h 55m 51.97s , -25d 28m 37.9s) |   C |    60 | 17.3 |        
   15595 | 2023-11-16 13:59:59 |        MASTER-Tunka | (01h 23m 39.29s , -27d 21m 52.5s) |   C |    60 | 17.4 |        
   16760 | 2023-11-16 14:19:24 |        MASTER-Tunka | (01h 39m 44.73s , -28d 05m 13.6s) |   C |    60 | 13.6 |        
   16760 | 2023-11-16 14:19:25 |        MASTER-Tunka | (01h 40m 42.06s , -27d 21m 29.3s) |   C |    60 | 16.2 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB231115A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35064
SUBJECT: GRB 231115A: Swift-XRT and Swift-UVOT observations
DATE:    23/11/16 14:39:58 GMT
FROM:    Phil Evans at U of Leicester <pae9@star.le.ac.uk>

J.P. Osborne (U. Leicester), B. Sbarufatti (INAF-OAB), A. D'Ai
(INAF-IASFPA), A. Melandri (INAF-OAR), J. D. Gropp (PSU), S. Dichiara
(PSU), J.A. Kennea (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U.
Leicester) and P.A. Evans (U. Leicester) and S. R. Oates (Lancaster U.)
report on behalf of the Swift-XRT and the Swift-UVOT teams:

Swift-XRT has performed follow-up observations of the INTEGRAL-detected
burst GRB 231115A, which is likely not a GRB, but it is likely a MGF
(Burns GCN Circular 35038) and whose position is consistent with M82
galaxy (D'Avanzo et al. GCN Circ. 35036; Mereghetti et al. GCN Circ.
35037), collecting 4.4 ks of Photon Counting (PC) mode data between
T0+9.0 ks and T0+39.2 ks.

No uncatalogued X-ray sources have been detected consistent with being
within 303 arcsec of the INTEGRAL position. The 3-sigma upper limit in
the field ranges from ~0.002 to ~0.003 ct s^-1, corresponding to a
0.3-10 keV observed flux of 8.2e-14 to 1.2e-13 erg cm^-2 s^-1 (assuming
a typical GRB spectrum).

Six previously-catalogued X-ray sources have been detected consistent
with being within 303 arcsec of the INTEGRAL position, however their
status as catalogued objects makes them unlikely to be the X-ray
counterpart.

An uncatalogued object was detected, however this was too far from the
GRB position to be the X-ray counterpart.

We note that the diffuse X-ray emission from the M82 galaxy affects a
significant fraction of the INTEGRAL error circle. This likely reduces
the sensitivity for source detection.

The results of the XRT-team automatic analysis of the XRT observations,
including a position specific upper limit calculator, are available at
https://www.swift.ac.uk/ToO_GRBs/00021625.

No optical counterpart consistent with the INTEGRAL position
(Mereghetti et al., GCN Circ. 35037) is detected in the initial UVOT
exposures.

Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) are:

Filter        T_start(s)   T_stop(s)    Exp(s)   Mag

w1     9253
       39224     4283 >17.4

The magnitude in the table is not corrected for the Galactic extinction

due to the reddening of E(B-V) = 0.155 in the direction of the burst
(Schlegel et al. 1998).



This circular is an official product of the Swift team.


GRB_name: GRB231115A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35065
SUBJECT: GRB 231115A: Swift/BAT-GUANO detection of a short burst
DATE:    23/11/16 17:46:12 GMT
FROM:    Samuele Ronchini at PSU <sjs8171@psu.edu>

Samuele Ronchini (PSU), Aaron Tohuvavohu (U Toronto), James DeLaunay (PSU), Gayathri Raman (PSU), Tyler Parsotan (NASA GSFC), Jamie A. Kennea (PSU) report: 

Swift/BAT did not localize GRB 231115A onboard (T0: 2023-11-15T15:36:21.2 UTC, Fermi GCN 35035, Integral GCN 35037, Glowbug GCN 35045, Insight-HXMT/HE GCN 35060, Konus-Wind GCN 35062).

The Fermi and Integral notices, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). 

Upon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground. 

The BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), performed on the temporal window [T0-20 s, T0+20 s], detects the burst with a sqrt(TS) of 20.26 in a 0.128 s analysis time bin, starting at T0.

NNITRATES results, independently, are ambiguous with respect to whether this burst originates from in or outside the BAT coded FOV, with a DeltaLLHOut of 8.9.
The Integral localization, coincident with M82, is consistent with being outside the BAT coded FOV.

The very short duration and the large E_peak (best fit value from the spectral template of 720 keV) are consistent with the Magnetar Giant Flare scenario (GCN 35044, GCN 35059).

See Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretation of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut. 

GUANO is a fully autonomous, extremely low latency, spacecraft commanding pipeline designed for targeted recovery of BAT event mode data around the times of compelling astrophysical events to enable more sensitive GRB searches. 

A live reporting of Swift/BAT event data recovered by GUANO can be found at: https://www.swift.psu.edu/guano/


GRB_name: GRB231115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35066
SUBJECT:  GRB 231115A: NuSTAR Follow-Up Observations
DATE:    23/11/16 18:55:44 GMT
FROM:    Brian Grefenstette at Caltech/NuSTAR <bwgref@srl.caltech.edu>

B. Grefenstette and M. Brightman (Caltech) for the NuSTAR Team

NuSTAR performed follow-up observations of GRB 231115A / magnetar giant flare (Burns GCN Circular 35038) in the direction of M82 (D'Avanzo et al. GCN Circ. 35036; Mereghetti et al. GCN Circ. 35037). The NuSTAR observation was centered on the potential optical counterpart location from GROWTH India (Kumar et al. GCN Circ 35041, Kumar et al., GCN Circ 35055).

NuSTAR began observing at 2023-11-15T22:21:09, only ~four hours after the ToO trigger was approved. We report on the first ~40-ks of data.

M82 has a number of bright point sources as well as extended emission that is unresolved by the NuSTAR PSF (see, e.g., Brightman et al 2020 ApJ 889 71, DOI:10.3847/1538-4357/ab629a). The NuSTR observation does not reveal any significant point sources outside of the central ~1-arcmin region of M82. No significant emission from the location of optical transient AT2023xvj at RA = 09:56:00.2, Dec = 69:40:29.2 (RA=149.000,Dec=+69.675) is seen, though this overlaps with the wings of the NuSTAR PSF from the central emission from M82 as well as extended emission in the galaxy. These observations are on-going.

The NuSTAR SINGS pipeline did not trigger on the GRB 231115A transient. We performed an off-line analysis of the NuSTAR shield data and the count rates from the X-ray detectors and do not see the transient in either set of data. This is unsurprising, as the NuSTAR CsI shield data are only stored at 1-Hz and short signals such as from this GRB are difficult to identify. The source was ~80 degrees from the Earth horizon and ~35-deg from the instrument boresight, which may also have been an unfavorable geometry for detecting the source in the CdZnTe detectors.


GRB_name: GRB231115A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35068
SUBJECT: MAGIC observation of GRB 231115A, a possible magnetar giant flare
DATE:    23/11/16 22:40:37 GMT
FROM:    dpaneque@mppmu.mpg.de

The MAGIC telescopes observed GRB 231115A (RA:09:56:00.22, Dec:+69:40:48.00), a candidate Magnetar Giant Flare from M82 (GCN 35044)  after the alert issued by INTEGRAL (GCN/INTEGRAL NOTICE 10427). The observations in the very-high-energy (VHE; >100 GeV) range were performed on the night of November 15th  starting at ~T0+8h, for about 2 hours, at large zenith angles.  The fast and preliminary analysis does not show any significant detection (<2 sigma) above 250 GeV.  The preliminary integral flux upper limit (95% confidence level)  at 300 GeV is 8e-12 cm-2 s-1.

The contact persons for the MAGIC collaboration are Alicia LÃ³pez-Oramas (alicia.lopez@iac.es), Alessandra Lamastra (alessandra.lamastra@inaf.it)  and Giuseppe Silvestri (giuseppe.silvestri@studenti.unipd.it). MAGIC is a system of two 17m-diameter Imaging Atmospheric Cherenkov Telescopes located at the Observatory Roque de Los Muchachos of the Instituto de AstrofÃ­Â­sica de Canarias (IAC) on the Canary island of La Palma, Spain (https://magic.mpp.mpg.de).


GRB_name: GRB231111A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35069
SUBJECT: GRB 231111A: Swift/UVOT Detection
DATE:    23/11/17 00:10:52 GMT
FROM:    Sam LaPorte at PSU <sjl5346@psu.edu>

GRB 231111A: Swift/UVOT Detection

S. J. LaPorte (PSU) and A. Melandri (INAF-OAR)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 231111A
165 s after the BAT trigger (Melandri et al., GCN Circ. 34981).
A source consistent with the XRT position
(Evans et al., GCN Circ. 34991)
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
    RA  (J2000) =  19:20:45.25 = 290.18856 (deg.)
    Dec (J2000) = +52:26:10.5  =  52.43624 (deg.)
with an estimated uncertainty of 0.43 arc sec. (radius, 90% confidence).

Preliminary detections using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)           Mag

b                   26598       27505        885         >20.41
uvm2                34150       34575        418         >20.05
u                     180         418        234          16.52
v                   33541       34144        590         >19.85
uvw1                38947       39736        776         >20.24
uvw2                27512       85141       1176         >20.65


The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.117 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB231115A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35070
SUBJECT: GRB 231115A: Non-detection of radio emission with CHIME/FRB
DATE:    23/11/17 00:23:15 GMT
FROM:    alice.curtin@mail.mcgill.ca

Alice P. Curtin (McGill University) for the CHIME/FRB Collaboration:

At 15:36:21 UTC on 15 November 2023, GRB 231115A was detected by Fermi/GBM (Fermi GBM Team, GCN 35035 & 35044), INTEGRAL (P. D'Avanzo et al., GCN 35036, S. Mereghetti et al., GCN 35037), Glowbug (C. C. Cheung et al., GCN 35045), and Insight-HXMT (Insight-HXMT team, GCN 35060). The position of GRB 231115A (RA=149.00, DEC=69.68 with an uncertainty of 2 arcmin) is consistent with that of the M82 galaxy (S. Mereghetti et al. GCN 35037). Additionally, the spectrotemporal properties of GRB 231115A suggest it is likely due to a magnetar giant flare (Fermi/GBM Team, GCN 35044, S. Ronchini et al., GCN 35065).

At the time of the high-energy (HE) emission, GRB 231115A was ~20 degrees from the meridian of the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst Project (CHIME/FRB). No radio emission was detected from the source at the time of the HE emission. In addition to searching for radio emission at the time of the Fermi/GBM trigger, we also searched within the CHIME/FRB database for bursts from this position within the last two years, yet did not find any definitive astrophysical associations.

Using a pipeline described in Curtin et al. (2023), we constrain the FRB-like radio emission from this source in the 400-800 MHz band to be <260 Jy or <720 Jy ms (assuming a 10 ms pulse width) at the time of the Fermi/GBM trigger. The HE fluence reported by Fermi/GBM in the 10-1000 keV range is (6.3 +/- 0.4)e-7 erg/cm^2  (Fermi/GBM Team, GCN 35044). This implies a radio-to-HE emission ratio of <4.5e-9 (unitless assuming a 400 MHz bandwidth). Additionally, using a luminosity distance of 3.5 Mpc to the M82 galaxy (P. D'Avanzo et al. 2023, GCN 35036), our derived radio flux limit corresponds to an upper limit on the radio luminosity of <3.8e30 erg s^-1 Hz^-1. 

While GRB 231115A was ~20 degrees from the meridian of CHIME/FRB at the time of the Fermi/GBM trigger, it transited directly overhead CHIME/FRB at 14:18:45 UTC on 15 November 2023. Thus, our best radio constraints for this source are ~80 minutes prior to the Fermi/GBM trigger. As no radio emission was similarly detected at this time, we constrain the radio flux at this time to be <0.5 Jy and the fluence to be <1.2 Jy ms assuming a burst width of 10 ms. This corresponds to a radio luminosity limit of <7.3e27  erg s^-1 Hz^-1 and a radio-to-HE fluence ratio of <7.6e-12 (unitless assuming a 400 MHz bandwidth). 

References
Curtin, A.P., Tendulkar, S.P., Josephy, A., et al., 2023, ApJ, 954, 154. doi:10.3847/1538-4357/ace52f


GRB_name: GRB231117A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35071
SUBJECT: GRB 231117A: Swift detection of a bright short burst
DATE:    23/11/17 03:16:38 GMT
FROM:    David Palmer at LANL <palmer@lanl.gov>


S. Laha (GSFC/UMBC), C. Gronwall (PSU), J.D. Gropp (PSU),
N. J. Klingler (GSFC/UMBC/CRESSTII), D. M. Palmer (LANL),
T. M. Parsotan (GSFC/UMBC/CRESSTII), C. Salvaggio (INAF-OAB) and
A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 03:03:19 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 231117A (trigger=1197027).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 332.409, +13.514 which is 
   RA(J2000) = 22h 09m 38s
   Dec(J2000) = +13d 30' 49"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single bright
peak structure with a duration of about 1.5 sec.  The peak count rate
was ~80,000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 03:05:01.5 UT, 101.8 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 332.39146, 13.52328 which is equivalent
to:
   RA(J2000)  = 22h 09m 33.95s
   Dec(J2000) = +13d 31' 23.8"
with an uncertainty of 4.3 arcseconds (radius, 90% containment). This
location is 69 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at https://www.swift.ac.uk/sper.  We
cannot determine whether the source is fading at the present time. No
spectrum from the promptly downlinked event data is yet available to
determine the column density. 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 105 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image processing
FAILED because of no aspect solution. Results from the list of sources
generated on-board are not available at this time. No correction has been made
for the expected extinction corresponding to E(B-V) of 0.071. 

Burst Advocate for this burst is S. Laha (sib.laha AT gmail.com). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB231117A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35072
SUBJECT: GRB 231117A: AstroSat CZTI detection of a bright short burst
DATE:    23/11/17 07:09:52 GMT
FROM:    Gaurav Waratkar at IIT Bombay <gauravwaratkar@iitb.ac.in>

P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a bright short duration GRB 231117A which was also detected by Swift-BAT (Laha et al., GCN Circ. 35071), and CALET (Trigger 1384225326).

The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2023-11-17 03:03:19.74 UTC. The measured peak count rate associated with the burst is 8467 (+1562, -767) counts/s above the background in the combined data of all quadrants, with a total of 1375 (+86, -77) counts. The local mean background count rate was 335 (+15, -38) counts/s. Using cumulative rates, we measure a T90 of 0.42 (+0.04, -0.06) s.

The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-11-17 03:03:18.82 UTC. The measured peak count rate associated with the burst is 1496 (+86, -96) counts/s above the background in the combined data of all quadrants, with a total of 1883 (+307, -334) counts. The local mean background count rate was 1497 (+6, -7) counts/s. Due to the intrinsic 1 s binning of Veto data, we cannot reliably estimate a T90 from it.

CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.

CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB231117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35073
SUBJECT: GRB 231117A: GOTO optical upper limits
DATE:    23/11/17 11:36:55 GMT
FROM:    Ben Gompertz at U of Birmingham <b.gompertz@bham.ac.uk>

B. Godson, K. Ackley, B. P. Gompertz, J. Lyman, M. Dyer, D. Steeghs, A. Kumar, A. J. Levan, R. Starling, F. JimÃ©nez-Ibarra, K. Ulaczyk, D. Galloway, V. Dhillon, P. O'Brien, G. Ramsay, K. Noysena, R. Kotak, R. Breton, L. Nuttall, E. PallÃ©, D. Pollacco, T. Killestein and D. O'Neill report on behalf of the GOTO collaboration:

The Gravitational-wave Optical Transient Observer (GOTO, Steeghs et al. 2022) performed a targeted observation in response to GRB 231117A (Laha et al., GCN 35071; Navaneeth et al, GCN 35072) at 10:00:02 UT on 2023-11-17, starting approximately 7 hours after trigger. The observation consisted of a 4x90s exposure in the GOTO L-band (400-700 nm).

Images were processed immediately after acquisition using the GOTO pipeline. No optical counterpart to the X-ray afterglow detected by Swift/XRT (Laha et al., GCN 35071) is seen to a 3-sigma limit of L > 20.4 magnitudes (AB).

Magnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and are not corrected for Galactic extinction.

GOTO (https://goto-observatory.org) is a network of telescopes that is principally funded by the STFC and operated at the Roque de los Muchachos Observatory on La Palma, Spain, and Siding Spring Observatory in NSW, Australia, on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory & Planetarium, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT), the University of Turku, the University of Portsmouth, the University of Manchester and the Instituto de Astrofisica de Canarias (IAC).


GRB_name: GRB231117A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35074
SUBJECT: GRB 231117A: Enhanced Swift-XRT position
DATE:    23/11/17 11:40:38 GMT
FROM:    Phil Evans at U of Leicester <pae9@star.le.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 2459 s of XRT Photon Counting mode data and 3 UVOT
images for GRB 231117A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 332.38988, +13.52255 which is equivalent
to:

RA (J2000): 22h 09m 33.57s
Dec (J2000): +13d 31' 21.2"

with an uncertainty of 2.0 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB231117A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35075
SUBJECT: GRB 231117A: AGILE detection of a bright short burst
DATE:    23/11/17 11:45:06 GMT
FROM:    Paolo Walter Cattaneo at INFN Pavia <paolo.cattaneo@pv.infn.it>

P.W. Cattaneo (INFN Pavia), F. Verrecchia (SSDC, and INAF/OAR), 
F. Longo (Univ. Trieste, and INFN Trieste), C. Pittori (SSDC, and INAF/OAR), 
C. Casentini (INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata),
A. Argan, M. Cardillo, Y. Evangelista, L. Foffano, G. Piano (INAF/IAPS),
A. Addis, L. Baroncelli, A. Bulgarelli, A. Ciabattoni, A. Di Piano, V. Fioretti 
(INAF/OAS-Bologna), G. Panebianco (Univ. Bologna - INAF/OAS Bologna), 
N. Parmiggiani (INAF/OAS-Bologna), F. Lucarelli (SSDC, and INAF/OAR),
M. Marisaldi (INAF/OAS-Bologna, and Bergen University), M. Pilia, A. Trois
(INAF/OA-Cagliari), A. Ursi (ASI and INAF/IAPS), I. Donnarumma, E. Menegoni 
(ASI), A. Giuliani (INAF/IASF-Mi), F. Cutrona (Univ. Milano Bicocca) and P. 
Tempesta (TeleSpazio) report on behalf of the AGILE Team:

The AGILE satellite detected the short GRB 231117A at T0 = 2023-11-17
03:03:20.50 (UT) , reported by Swift (GCN #35071) and AstroSat (GCN #35072).

A preliminary analysis of the AGILE minicalorimeter (MCAL) triggered data
found a  burst at T_mcal = 2023-11-17 03:03:20 +/- 0.01 s (UTC).

The event lasted about 0.16 s and released a total number of 222 counts
in the detector (in the 0.4-100 MeV energy range), above an average
background rate of 364 counts/s.

The light curve can be found at:
http://www.agilescienceapp.it/notices/086277-086279_GRB_MCAL_627274999.673711.png.

The AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive in
the energy range 0.4-100 MeV. Additional analysis of AGILE data is in progress.


GRB_name: GRB231117A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35076
SUBJECT: GRB 231117A : MITSuME Akeno optical upper limits
DATE:    23/11/17 12:25:57 GMT
FROM:    takei@hp.phys.titech.ac.jp

H. Takei, N. Higuchi, I. Takahashi, M. Sasada, M. Niwano, S. Sato, S. Hayatsu, H. Seki, Y. Yatsu and N. Kawai  (Tokyo Tech) report on behalf of the MITSuME collaboration:

We observed the field of GRB 231117A (Laha et al. GCN Circular #35071) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope Akeno. 

The observation started at 2023-11-17 08:14:35 UT (5.19 hours after the Swift/BAT trigger). We stacked the images with good conditions. We did not detect any uncatalogued sources within the enhanced Swift/XRT error region (Beardmore et al. GCN Circular #35074). We obtained the 5-sigma limits of the stacked images as follows.

T0+[hour] | MID-UT | T-EXP[sec] | 5-sigma limits
------------------------------------------------------------------------------------------------
6.38 | 2023-11-17 09:25:57 | 5160 | g'>19.9, Rc>19.9, Ic>19.3
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the trigger
T-EXP: Total Exposure time

We used the PS1 catalog for flux calibration. The catalog magnitudes in PS1 g, r and i bands were converted to our g', Rc and Ic band magnitudes following Tonry et al. (2012), Table 6. The magnitudes are expressed in the AB system. The images were processed in real-time through the MITSuME GPU reduction pipeline (Niwano et al. 2021, PASJ, Vol.73, Issue 1, Pages 4-24; https://github.com/MNiwano/Eclaire).


GRB_name: GRB231115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35077
SUBJECT: GRB 231115A: optical observations from INAF observatories
DATE:    23/11/17 13:48:03 GMT
FROM:    Paolo D'Avanzo at INAF-OAB <pda.davanzo@gmail.com>

P. D'Avanzo (INAF-OAB), A. Reguitti (INAF-OAB / INAF-OAPd), L. Tomasella (INAF-OAPd), E. Cappellaro (INAF-OAPd), M. T. Botticella (INAF-OAC), F. Onori (INAF-OAAb), L. Tartaglia (INAF-OAAb), F. De Luise (INAF OAAB), M. G. Bernardini (INAF-OAB), S. Campana (INAF-OAB), S. Covino (INAF-OAB), V. D'Elia (ASI/SSDC & INAF/OAR), M . De Pasquale (Univ. of Messina), D. B. Malesani (DAWN/NBI & Radboud Univ.), E. Palazzi (INAF-OAS), A. Rossi (INAF-OAS), R. Salvaterra (INAF-IASF Mi), G. Tagliaferri (INAF-OAB), A. Melandri (INAF-OAR), E. Brocato (INAF-OAAb), M. Pedani, C. P. Padilla-Torres (INAF/TNG) report on behalf ot the CIBO and of the GRAWITA collaborations:


We carried out follow-up optical observations of the high-energy event detected by Fermi/GBM, INTEGRAL, Glowbug, Insight-HMXT/HE, Konus-Wind, Swift/BAT on 2023-11-15 at 15:36:21 UT, initially classified as the short/hard GRB 231115A and subsequently as a likely magnetar giant flare located in the M82 galaxy (Fermi GBM team, GCN Circ. 35035; D'Avanzo et al., GCN Circ. 35036; Mereghetti et al., GCN Circ. 35037; Dalessi et al., GCN Circ. 35044; Cheung et al., GCN Circ. 35045; Xue et al. GCN Circ. 35060; Frederiks et al., GCN Circ. 35062; Ronchini et al., GCN Circ. 35065). 

Observations from the INAF - Padova Astronomical Observatory located in Asiago (Italy) have been carried out with the Schmidt telescope starting on 2023-11-15 at 20:40:03 UT (~ 5 hours after the event T0) with the g, r and i filters. 
Preliminary analysis, which includes image subtraction with SDSS templates, does not show evidence for promising candidate counterparts within the INTEGRAL error circle (Mereghetti et al., GCN Circ. 35037). 
The typical 3sigma limiting AB magnitudes at the position of the candidate counterpart AT2023xfj (Kumar et al., GCN Circ. 35041 and 35055) are g ~ 19.5 mag, r ~ 18.4 mag and i ~ 20.3 mag. 


Observations the from INAF - Abruzzo Astronomical Observatory located in Campo Imperatore (Italy) have been carried out starting on 2023-11-15 at 21:38:00 UT (~ 6 hours after the event T0) with the g, i and z filters.  
Preliminary analysis, which includes image subtraction with SDSS templates, does not show evidence for promising candidate counterparts within the INTEGRAL error circle. 
The typical 3sigma limiting AB magnitudes at the position of the candidate counterpart AT2023xfj are g ~ 18.7 mag, i ~ 17.2 mag and z ~ 17.2 mag. 


Observations the from INAF - TNG located in Canary Islands (Spain) have have been carried out starting on 2023-11-16 at 03:27:28 UT (~ 12 hours after the event T0) with the r, i and z filters.  
Preliminary analysis, which includes image subtraction with SDSS and archival TNG templates, does not show evidence for promising candidate counterparts within the INTEGRAL error circle. 
The typical 3sigma limiting AB magnitude at the position of the candidate counterpart AT2023xfj in the r filter is of ~ 22.0 mag. 


GRB_name: GRB231115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35078
SUBJECT: GRB 231115A : OHP/T120 optical upper limit
DATE:    23/11/17 14:17:47 GMT
FROM:    Damien Turpin at CEA-Saclay <dturpin-astro@hotmail.com>

D. Turpin (CEA Paris-Saclay), W. Thuillot (Obs. Paris/IMCCE), D. Souami (Obs. Paris/LESIA), C. Adami (LAM), E. Le Floc'h, D. GÃ¶tz, F. SchÃ¼ssler (CEA Paris-Saclay), A. de Ugarte Postigo (OCA/CNRS), S. Basa (Pytheas/OHP/LAM), S. D. Vergani (GEPI, Obs. de Paris), report on behalf of a larger collaboration:

We observed the field of GRB 231115A, likely a Giant flare from a magnetar in M82 (Fermi GBM Team, GCN 35035; Mereghetti et al., GCN 35037, Dalessi et al. GCN 35044, Cheung et al. GCN 35045, Xue et al., GCN 35060, Frederiks et al. GCN 35062) using the T120cm telescope at Observatoire de Haute-Provence (France). We began our observations of the M82 field on 2023 15 November 22:57:23.78 (~7.35h after the INTEGRAL trigger time) with a series of R-band (1400s), V-band (600s) and sdss-i (300s) images. The limiting magnitudes of our images are R> 21.1, V>20.9 and i>19.2 but are strongly reduced in the vicinity of M82 due to its bright diffuse background light.

After inspecting our residual images from the subtraction of both the PS1 catalog images and our archival own M82 images, we do not detect any new source inside the INTEGRAL localization. We also  do not detect any credible counterpart at the location of the transient candidate reported by Kumar et al. GCN 35041.

The photometric calibration was performed using nearby stars from the PanSTARRS catalog and the magnitude is not corrected for Galactic extinction.

We acknowledge the excellent support from Observatoire de Haute-Provence. 


GRB_name: GRB231117A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35079
SUBJECT: Konus-Wind detection of GRB 231117A (short/hard)
DATE:    23/11/17 14:21:53 GMT
FROM:    Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>

D. Svinkin, D. Frederiks, A. Lysenko, A. Ridnaia,
Yu. Temiraev, A. Tsvetkova, M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:

The bright, short-duration GRB 231117A
(Swift-BAT detection: Laha et al., GCN Circ. 35071;
AstroSat-CZTI detection: Navaneeth et al., GCN Circ. 35072;
AGILE-MCAL detection: Cattaneo et al., GCN Circ. 35075)
triggered Konus-Wind at T0=10998.926 s UT (03:03:18.926).

The burst light curve shows a single pulse
which starts at ~T0 and has a total duration of ~0.7 s.
The emission is seen up to ~10 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB231117_T10998/

As observed by Konus-Wind, the burst
had a fluence of 9.10(-0.94,+0.97)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0+0.052 s,
of 5.88(-1.01,+1.03)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+0.256 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -1.15(-0.11,+0.13),
the high energy photon index beta = -2.81(-7.19,+0.43),
the peak energy Ep = 400(-82,+89) keV
(chi2 = 45/51 dof).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB231117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35080
SUBJECT: GRB 231117A: ATLAS non-detection of an optical counterpart
DATE:    23/11/17 14:22:29 GMT
FROM:    James Gillanders at University of Oxford <jhgillanders.astro@gmail.com>

J. H. Gillanders (Oxford), S. J. Smartt, S. Srivastav (Oxford/QUB), M. D. Fulton, K. W. Smith, A. Aamer, C. R. Angus, M. McCollum, T. Moore, M. Nicholl, X. Sheng, J. Weston, D. R. Young (QUB), P. Ramsden (QUB/Birmingham), L. Shingles (GSI/QUB), A. Andersson, S. Ramaiya, L. Rhodes, H. Stevance (Oxford), J. Sommer (LMU/QUB), L. Denneau, J. Tonry, H. Weiland, A. Lawrence, R. Siverd (IfA, University of Hawaii), N. Erasmus, W. Koorts (South African Astronomical Observatory), A. Jordan, V. Suc (UAI, Obstech), A. Rest (STScI), T.-W. Chen (NCU), C. Stubbs (Harvard).

Here we report optical observations in the field of the Swift-BAT discovered GRB 231117A (Laha et al. GCN Circ. 35071), obtained during normal survey operations with ATLAS.

ATLAS is a quadruple 0.5-m telescope system with two units in Hawaii, one in Chile and one in South Africa (see Tonry et al. 2018, PASP, 130:064505), routinely surveying the visible sky on a daily basis. We promptly process all data with our transient science server (Smith et al. 2020, PASP, 132:085002).

The ATLAS system observed the field of the GRB 231117A in normal survey mode 3.3-hr after the GRB trigger date of MJD 60265.127 (=2023-11-17 03:03:19 UT, hereafter T0). We obtained forced photometry at the enhanced Swift-XRT X-ray source coordinates of RA = 332.38988, Dec = +13.52255 (Beardmore et al. GCN Circ. 35074). We found no historical detections of any excess optical flux at this position, or at any location within the XRT and BAT error regions.

Forced photometry at those coordinates results in the following most recent non-detection in the ATLAS c-band. These measurements are not corrected for any Galactic dust extinction.

Exp. time (s) = 120 (4 x 30)
MJD = 60265.310 (T0 + 3.3-hr)
Flux (uJy) < 19 (3-sigma)
Mag (AB) > 20.7 (3-sigma)


GRB_name: GRB231117A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35081
SUBJECT: GRB 231117A (short): Glowbug gamma-ray detection
DATE:    23/11/17 15:20:49 GMT
FROM:    C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>

C.C. Cheung, M. Kerr, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:                                                                                                                                                                                                                                                    

The Glowbug gamma-ray telescope [1,2], operating on the International Space Station, reports the detection of the short burst, GRB 231117A, which was also detected by Swift/BAT, AstroSat/CZTI, AGILE, and Konus/Wind (GCN 35071, 35072, 35075, 35079). 

Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2023-11-17 03:03:18.592 with a duration of 1.024 s and a total significance of about 124.0 sigma. The light curve comprises a single FRED-shaped pulse.

Using a standard power-law function with an exponential high-energy cutoff [3] to model the emission over this duration results in a photon index dN/dE~E^x of x=0.2 and a cutoff energy ("Epeak") of 461 keV.  The modeled 10-10000 keV fluence is 5.1e-06 erg/cm^2.

The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.

Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC.  It was launched on 2023 March 15 aboard the Department of Defense Space Test Programâ€™s STP-H9 to the ISS.  The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2/3 sky) over a wide energy band of 50 keV to >2 MeV.

[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006

Distribution Statement A: Approved for public release.  Distribution is unlimited.


GRB_name: GRB231117A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35082
SUBJECT: Swift GRB 231117A: Global MASTER-Net observations report
DATE:    23/11/17 15:42:59 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),

D. Buckley
(South African Astronomical Observatory),

O.A. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),

V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)

MASTER-Kislovodsk robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the Swift GRB 231117A ( S. Laha et al., GCN 35071) errorbox  44404 sec after notice time and 44429 sec after trigger time at 2023-11-17 15:23:48 UT, with upper limit up to  19.2 mag. The observations began at zenith distance = 29 deg. The sun  altitude  is -17.8 deg. 

The galactic latitude b = -34 deg., longitude l = 74 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2307518

We obtain a following upper limits.  

Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

   44519 |   MASTER-Kislovodsk |   C |   180 | 18.0 |        
   44519 |   MASTER-Kislovodsk |   C |   180 | 17.9 |        
   44920 |   MASTER-Kislovodsk |   C |   180 | 18.5 |        
   44920 |   MASTER-Kislovodsk |   C |   180 | 19.2 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.


GRB_name: GRB231117A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35083
SUBJECT: GRB 231117A: afterglow candidate detection from Kinder observations with Lulin observatory
DATE:    23/11/17 16:16:49 GMT
FROM:    Ting-Wan Chen at MPE <janet.chen@astro.su.se>

S. Yang (HNAS), T.-W. Chen, C.-S. Lin, C.-C. Ngeow (NCUIA), Z.-N. Wang (HNAS), S. Smartt (Oxford/QUB), M. Fraser (UCD), J. Gillanders (Oxford), M.-H. Lee, Y.-C. Pan, H.-Y. Hsiao, W.-J. Hou, J.-K. Guo (NCUIA), M. Fulton, S. Srivastav, T. Moore, C. Angus, and A. Aamer (QUB) report:

We observed the field of GRB 231117A, a bright, short GRB discovered by the Swift BAT (Laha et al., GCN 35071). This burst is also detected by AstroSat (Navaneeth et al., GCN 35072), AGILE (Cattaneo et al., GCN 35075), Konus-Wind (Svinkin et al., GCN 35079), and Glowbug (Cheung et al., GCN 35081).

We used the 40cm SLT at Lulin Observatory, Taiwan to obtain r-band images of the field of GRB 231117A, as part of the Kinder collaboration (Chen et al., AstroNote 2021-92). The first SLT epoch of observations started at 10:26 UT on 17 of November 2023 (MJD = 60265.435), 7.39 hours after the Swift trigger. The images were combined from 14 frames with a 300-second exposure time for the r band, taken under seeing conditions of an average of 1".93 and at a median airmass of 1.02. We then used the Lulin One-meter Telescope (LOT) to obtain g, r, i, and z-band images of this field starting on MJD = 60265.520, under seeing conditions of an average of 1".39 and at a median airmass of 1.21.

We found a GRB afterglow candidate at the position:

RA (J2000): 22h 09m 33.37s
Dec (J2000): +13d 31' 20.2â€

which is about 3" away from the enhanced Swift-XRT position (Beardmore et al., GCN 35074). This afterglow condidate is right on the top of the faint galaxy, SDSS J220933.34+133119.5, with a petroMag_r = 21.32 +/- 0.22 mag. The likely host galaxy has a SDSS photo-z of 0.481 +/- 0.103 and a Legacy Survey photo-z of 0.342 +/- 0.131.

We used the Kinder pipeline (Yang et al. A&A 646, A22) to measure the PSF photometry of this afterglow candidate after template subtraction using the SDSS images. We obtained the following magnitudes (in the AB system):

SLT r = 20.94 +/- 0.10 mag (exposure time of 300sec*14)
LOT g = 20.90 +/- 0.10 mag (300sec*1),
LOT r = 20.77 +/- 0.07 mag (300sec*7),
LOT i = 20.52 +/- 0.11 mag (300sec*1) and,
LOT z = 20.00 +/- 0.18 mag (SNR=2; 300sec*1).

The given limit is derived based on calibrating against SDSS field stars and is not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V) = 0.06 mag in the direction of the burst (Schlafly & Finkbeiner 2011).

Our detection magnitudes are deeper than those non-detection reports from the GOTO (Godson et al., GCN 35073), MITSuME (Takei et al., GCN 35076) and ATLAS (Gillanders et al., GCN 35080).


GRB_name: GRB231117A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35084
SUBJECT: GRB 231117A: AKO Optical Upper Limit
DATE:    23/11/17 16:43:21 GMT
FROM:    Mohammad Odeh at Al Khatim Observatory M44 <mshodeh@gmail.com>

M. Odeh (Al-Khatim Observatory, AKO, operated by the International
Astronomical Center in Abu Dhabi, UAE) and N. Guessoum and D. Akl (American
University of Sharjah, UAE) report:


We observed the field of GRB 231117A, which was detected by Swift/BAT,
AstroSat/CZTI, AGILE, and Konus/Wind (GCN 35071, 35072, 35075, 35079) with
our 0.36m f/7.7 robotic telescope on November 17 starting at: 14:46:29 UT
(corresponding to 11.72 hours from the GRB trigger time) using an (Ic)
filter. We obtained 33x180 second images.


We do not detect a source within the Swift-XRT error region around the
candidate X-ray source (Laha et al., GCN 35071). The following 5-sigma
upper limit is calculated using the ATLAS catalog as a reference:

Ic = 20.2.

We should note, however, that a star of Imag = 21.5 (AB) was barely
detected and is located at the position R.A. (2000) = 22 09 33.34, Dec.
(2000) = +13 31 19.44, that is about 2 arcseconds from the location of GRB
231117A, as per Pan-STARRS (PS1, ID = 124223323889577032).


GRB_name: GRB231117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35085
SUBJECT: GRB231117A: AGILE/MCAL analysis 
DATE:    23/11/17 16:47:51 GMT
FROM:    Claudio Casentini at INAF-IAPS <claudio.casentini@inaf.it>

C. Casentini (INAF/IAPS), F. Verrecchia (SSDC, and INAF/OAR), P.W. Cattaneo (INFN Pavia), F. Longo (Univ. Trieste, and INFN Trieste), C. Pittori (SSDC, and INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), A. Argan, M. Cardillo, Y. Evangelista, L. Foffano, G. Piano (INAF/IAPS), L. Baroncelli, A. Bulgarelli, A. Ciabattoni, A. Di Piano, V. Fioretti (INAF/OAS-Bologna), G. Panebianco (Univ. Bologna - INAF/OAS Bologna), N. Parmiggiani (INAF/OAS-Bologna), F. Lucarelli (SSDC, and INAF/OAR),  M. Marisaldi (INAF/OAS-Bologna, and Bergen University), M. Pilia, A. Trois (INAF/OA-Cagliari),  A. Ursi (ASI and INAF/IAPS), I. Donnarumma, E. Menegoni (ASI),  A. Giuliani (INAF/IASF-Mi), F.  Cutrona (Univ. Milano Bicocca) and P. Tempesta (TeleSpazio)  report on behalf of the AGILE Team:

We carried out further analysis of the AGILE/MCAL data of GRB 231117A (GCNs #35071, #35072, #35073, #35074, #35075, #35076, #35079, #35080, #35081, #35082, #35083, #35084).

The burst released 415 counts in the detector in 0.14s, above a background rate of 532 Hz.

The spectral analysis shows a clear component up to 5 MeV.

The time-integrated spectrum of the burst can be fitted in the energy range 0.4-2.0 MeV with a power-law model with alpha = -2.3 (+/-0.2). The fit results in a reduced chi-squared of 1.204 (21 d.o.f.) and a fluence of 2.4e-06 erg/cm^2, in the energy range 0.4-10 MeV.

Additional analysis of AGILE data is in progress. Automatic MCAL GRB alert Notices can be found at: 
https://gcn.gsfc.nasa.gov/agile_mcal.html.


GRB_name: GRB231117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35086
SUBJECT: GRB 231117A: REM optical and NIR early-time observations
DATE:    23/11/17 18:20:43 GMT
FROM:    Paolo D'Avanzo at INAF-OAB <pda.davanzo@gmail.com>

M.Ferro, R. Brivio, P. D'Avanzo, S. Covino, D. Fugazza (INAF-OAB) on behalf of the REM team, report:

We observed the field of GRB 231117A (Laha et al., GCN 35071) with the REM 60cm robotic telescope located at the ESO observatory of La Silla (Chile). The observations were carried in the g, r, i, z, J, H, K bands, starting on 2023 November 17 at 03:04:27 UT (i.e. 68 seconds after the burst) at airmass ~ 3, and lasting for about 2 hours.

From a preliminary analysis, we find no source at the enhanced XRT position (Beardmore et al., GCN 35074) at a mid time of t-t0 = 5.6 min, down to the following 3sigma magnitude upper limits:

r > 18.6
i > 17.9
z > 16.7
(AB; calibrated against the Pan-STARRS catalogue).


GRB_name: GRB231117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35087
SUBJECT: GRB 231117A: Keck observations indicate presence of optical afterglow in z~0.3-0.5 galaxy
DATE:    23/11/17 21:56:10 GMT
FROM:    Jillian Rastinejad at Northwestern Univ. <jillianrastinejad2024@u.northwestern.edu>

J. C. Rastinejad, W. Fong, H. Sears (Northwestern), R. Chornock, W. Jacobson-Galan (UC Berkeley), C. D. Kilpatrick (Northwestern), R. Margutti (UC Berkeley), G. Schroeder (Northwestern) et al. report:

''We observed the location of the bright short-duration GRB 231117A (Laha et al., GCN 35071, Navaneeth et al., GCN 35072, Cattaneo et al., GCN 35075, Svinkin et al., GCN 35079, Cheung et al., GCN 35081) with the Low Resolution Imaging Spectrometer (LRIS) mounted on the Keck I 10-meter telescope on Mauna Kea, Hawaii (PI Margutti). We obtain 6x150s of imaging in the g- and I-bands starting at 2023 Nov 17.096 UT (2.3 hr post-burst) at an airmass of 1.02 in 0.8'' seeing and thin clouds.

We detect the archival source (SDSS J220933.34+133119.5, photo-z = 0.34-0.48) first noted by Yang et al. (GCN 35083). This source is on the outskirts of the latest XRT position (Beardmore et al., GCN 35074). Calibrated to Pan-STARRS, we measure g = 20.3 +/- 0.1 mag and I = 19.8 +/- 0.1 mag (AB system and not corrected for Galactic extinction). These magnitudes are ~1.3.-1.5 mag brighter than the Pan-STARRS catalog magnitudes for this source across both filters. Although visual inspection does not indicate a clear physical separation between an afterglow and the center of the host, we attribute the clear brightening in flux to the optical afterglow, supporting the afterglow candidate discovered by Yang et al., and an origin for this short GRB at z~0.3-0.5.

Performing differential photometry relative to the Pan-STARRS catalog magnitudes results in an afterglow brightness of g~20.7 mag and I~20.1 mag at the time of our Keck observations. At z=0.4, this translates to an optical luminosity of ~7e43 erg/s, consistent with optical afterglow luminosities at similar rest-frame times. Taken at face value, our observations also indicate a slow decline rate (Fopt ~ t^-0.2 - t^-0.3) compared to the Lulin Observatory observations at 7.5 hr, although we caution that our preliminary analysis is only based on differential photometry and not image subtraction.

We encourage follow-up to determine the sourceâ€™s redshift and confirm the fading of the optical afterglow candidate."


GRB_name: GRB231117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35088
SUBJECT: GRB 231117A: LT observations consistent with fading
DATE:    23/11/17 22:43:55 GMT
FROM:    Ben Gompertz at U of Birmingham <b.gompertz@bham.ac.uk>

B. P. Gompertz (U. Birmingham) and K. Ackley (U. Warwick) report:

We observed the field of the short GRB 231117A (Laha et al., GCN 35071; Navaneeth et al., GCN 35072; Cattaneo et al., GCN 35075; Svinkin et al., GCN 35079; Cheung et al., GCN 35081) with the IO:O camera on the 2m robotic Liverpool Telescope. Observations began at 19:18:59 UT on 2023-11-17, ~16.3 hours after trigger, and consisted of 20x120s exposures in each of the SDSS r and i filters.

At the position of the optical counterpart reported by Yang et al. (GCN 35083) we detect a source with preliminary AB magnitudes of:

i = 20.10 +/- 0.03
r = 20.24 +/- 0.02

While these magnitudes include the contribution from the underlying galaxy, a comparison to the Keck observations taken ~14 hours prior (Rastinejad et al., GCN 35087) indicates fading at around the 3-sigma level. Combined with the significant excess above archival magnitudes, this supports the presence of the optical afterglow of GRB 231117A.

Analysis is ongoing. Reported magnitudes are not corrected for Galactic foreground extinction.


GRB_name: GRB231117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35089
SUBJECT: GRB 231117A: GIT optical follow-up
DATE:    23/11/18 01:51:44 GMT
FROM:    Vishwajeet Swain at IIT Bombay <vishwajeet.s@iitb.ac.in>

R. Kumar, A. Salgundi, V. Swain, V. Bhalerao (IIT Bombay), G. C. Anupama, S. Barway (IIA), R. Norboo (IAO)

We observed the field of GRB 231117A detected by Swift (S. Laha et al., GCN 35071) with 0.7m GROWTH-India Telescope (GIT). We started the observation at 2023-11-17 13:36:59 UT, i.e., 10.56 hours after the Swift trigger. We obtained the multiple images of 300s each in the r' and g' band. We did not detect any source within the uncertainty radius of Swift-XRT position reported by A.P. Beardmore et al., GCN 35074 upto a limiting magnitude of 22.38 in r' band. We do detect the candidate optical afterglow in our subtracted image at the position reported by Yang et al. (GCN 35083). The photometry values are given below:

------------------------------------------------------------------------

| JD (mid) | t-t0 (days) | Filter | Exposure (s) | Magnitude (5 sigma) |

------------------------------------------------------------------------

| 2460266.072780335 | 0.445 | r' | 3 x 300 | 20.80 +/- 0.06 | 
| 2460266.087725621 | 0.460 | r' | 3 x 300 | 21.18 +/- 0.08 | 
| 2460266.098941961 | 0.471 | r' | 3 x 300 | 20.88 +/- 0.07 | 
| 2460266.203419748 | 0.576 | r' | 3 x 300 | 20.84 +/- 0.07 | 
| 2460266.253062681 | 0.625 | g' | 2 x 300 | 20.88 +/- 0.07 |

------------------------------------------------------------------------

Our data shows slight variability in the source, but no clear decay. The results are comparable to the values reported by B. P. Gompertz et al., GCN 35088; J. C. Rastinejad et al., GCN 35087; Yang et al., GCN 35083; and consistent with the upper limits given by M.Ferro et al., GCN 35086; M. Odeh et al., GCN 35084; J. H. Gillanders et al., GCN 35080; H. Takei., GCN 35076; B. Godson et al., GCN 35073. Based on these measurements, we conclude that this source is unlikely to be the afterglow. The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction.

The GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/.


GRB_name: GRB231115A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35091
SUBJECT: GRB 231115A: JinShan optical upper limits
DATE:    23/11/18 02:05:01 GMT
FROM:    Dong Xu at NAOC/CAS <dxu@nao.cas.cn>

J. An, S.Q. Jiang, X. Liu, S.Y. Fu, Z.P. Zhu, T.H. Lu, D. Xu (NAOC), J.Z. Liu (XAO) report on behalf of a large collaboration:

We observed the field of GRB 231115A detected by the Fermi GBM (Fermi GBM Team, GCN 35035), INTEGRAL (Mereghetti et al., GCN 35037), and Glowbug (Cheung et al., GCN 35045), using two 50cm telescopes (50A, 50B) located at Altay, Xinjiang, China. Observations started at 17:30:51 UT on 2023-11-15, i.e., 1.91 hr after the Fermi/GBM trigger, in the Sloan g-/r-/i-/z- bands.

No credible optical transient is detected in our stacked images within and beside the error region of the INTEGRAL. Preliminary results are as follows:
-----------------------------------------------------------------
              Tmid(UT)      exp(s)   filter      UL(3-sigma)
-----------------------------------------------------------------
2023-11-15T17:47:17  60sx30      g           20.4
2023-11-15T18:20:18  60sx30      r            20.3
2023-11-15T18:34:16  30sx60      i            18.1
2023-11-15T17:54:39  30sx66      z           16.0
-----------------------------------------------------------------

calibrated with nearby PanSTARRS stars. The magnitude is not corrected for Galactic extinction. The z-band upper limit is shallower than expected due to a technical issue.

Altay Astronomical Time-Domain Project (JinShan Project for short) consists of four 50cm telescopes with FOV of 1.7x1.7 deg^2 for each (50A, 50B, 50C, and 50D), two 100cm telescopes with FOV of 1.4x1.4 deg^2 for each (100A and 100B), and one 100cm telescope with FOV of 14x14 arcmin^2 (100C). Each telescope is equipped with different filters. JinShan is now at its early commissioning stage.


GRB_name: GRB231115A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35092
SUBJECT: GRB 231115A: Wendelstein Optical/Infrared Observations
DATE:    23/11/18 04:18:45 GMT
FROM:    Antonella Palmese at Carnegie Mellon University <apalmese@andrew.cmu.edu>

Lei Hu (CMU), Malte Busmann (LMU), Daniel Gruen (LMU),  Antonella Palmese (CMU), Brendan Oâ€™Connor (CMU), Arno Riffeser (LMU/MPE), Ananya Shankar (LMU), Raphael Zoeller (LMU) report:

We observed the position of GRB 231115A (Fermi GBM team, GCN 35035) with the 2m Fraunhofer telescope at Wendelstein Observatory, Germany. Observations were obtained using the 3kk imager in the r, i, and J bands simultaneously, and then in r, i, and H bands. Observations started on 2023-11-16 at 00:39 UT with a total exposure time of 7200 seconds in r and i, and 3600 seconds in J, H.

We performed difference imaging in r band with deep archival Wendelstein Wide Field Imager observations of M82 using the SFFT pipeline (Hu et al. 2022). We do not detect any source at the location of GIT231115AA / AT2023xvj (Kumar et al, GCN 35041) to depth r> 22.5 (5sigma depth). We identify 2 new sources:

Name | RA (J2000 deg) | dec (J2000 deg) | r (AB mag)
----------------------
W231115a | 148.9711390 | 69.6730597 | 20.54 +/- 0.04
W231115b | 148.9950500 | 69.6912555 | 21.26 +/- 0.08 

W231115a is also detected in i, J, and H, while W231115b is only detected in r and i. We cannot exclude that these are variable objects associated with previously detected sources in archival HST data. Further analysis is underway.

The magnitudes are not corrected for Milky Way extinction and the photometry was calibrated against nearby stars in the PS1 and 2MASS catalogs. We thank the staff of the Wendelstein Observatory for obtaining these observations.


GRB_name: GRB231117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35093
SUBJECT: GRB 231117A: Keck spectroscopy of afterglow candidate
DATE:    23/11/18 06:10:57 GMT
FROM:    Tomas Ahumada Mena at Caltech <tahumada@caltech.edu>

Tomas Ahumada, Yashvi Sharma(Caltech) on behalf of a larger collaboration: 

We report optical spectroscopic observations of the candidate counterpart of the short GRB 231117A (GCN 35083, 35071) with the Low Resolution Imaging Spectrometer (LRIS, Oke et al. 95) at the Keck I Observatory (C358, PI: Kasliwal). Observations started 2023-11-18 05:19:00 (~1.1 days after the burst), and consisted of 2x900 exposures with the 400/3400 grism and 400/8500 grating.

The spectrum shows narrow galaxy lines at redshift of z = 0.257 (H, [O II], [O III], N II). We also see narrow absorption lines consistent with MgII(2796,2803) doublet at this redshift. We note the spectrum shows a blue continuum. 

We thank Michael Lundquist and the Keck team for their support during this Target of Opportunity trigger.

The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.


GRB_name: GRB231117A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35095
SUBJECT: GRB 231117A: GRBAlpha detection
DATE:    23/11/18 09:27:43 GMT
FROM:    Marianna DafÄÃ­kovÃ¡ at Masaryk University <500025@mail.muni.cz>

M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal,  A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), yyT. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory),  T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.

The short-duration GRB 231106B (Swift/BAT detection: GCN 35071; AstroSat detection: GCN 35072; AGILE/MCAL detection: GCN 35075; Konus/Wind detection: GCN 35079; Glowbug detection: GCN 35081; CALET/CGBM detection: trigger no. 1384225326) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023, A&A, 677, 40; arXiv:2302.10048).

The detection was confirmed at the peak time 2023-11-17 03:03:19 UTC. The T90 duration measured by GRBAlpha is 1 s and the overall significance during T90 reaches 14 sigma.

The light curve obtained by GRBAlpha is available here: https://grbalpha.konkoly.hu/static/share/GRB231117A_GCN.pdf

All GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ 
GRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume. 


GRB_name: GRB231117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35097
SUBJECT: GRB 231117A: ATCA detection of a radio counterpart
DATE:    23/11/18 10:44:18 GMT
FROM:    Lauren Rhodes at Oxford <lauren.rhodes@physics.ox.ac.uk>

L. Rhodes (Oxford), G. E. Anderson (Curtin), A. J. van der Horst (GWU),J. K. Leung (UofT/HUJI), S. D. Ryder (Macquarie),  A. Gulati (USyd), S. Chastain (UNM) on behalf of the PanRadio GRB collaboration



The Australia Telescope Compact Array (ATCA) observed short GRB 231117A (Laha et al., GCN 35071) as part of the Large ATCA "PanRadio GRB" follow-up programme C3542 (PI. Anderson) starting at 2023-11-17 04:00UT for 11hours.



We detect a radio source with a flux density of ~210uJy/beam at 9GHz at coordinates consistent with both those given by the XRT and the Lulin Observatory (A.P. Beardmore et al., GCN 35074; S. Yang et al., GCN 35083).



Further observations are planned.



We thank the CSIRO Space and Astronomy staff for supporting these observations.

We acknowledge the Gomeroi people as the traditional owners of the Observatory site. The Australia Telescope Compact Array is part of the Australia Telescope National Facility (https://ror.org/05qajvd42) which is funded by the Australian Government for operation as a National Facility managed by CSIRO.


GRB_name: GRB231117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35098
SUBJECT: GRB 231117A: ePESSTO+ host galaxy redshift confirmation
DATE:    23/11/18 13:08:05 GMT
FROM:    Daniele B. Malesani at IMAPP / Radboud University <d.malesani@astro.ru.nl>

M. Gonzalez-BaÃ±uelos, M. Kopsacheili (ICE), P. D'Avanzo (INAF-OAB), D. B. Malesani (DAWN/NBI and Radboud univ.), L. Galbany, T. MÃ¼ller-Bravo (ICE),  C. Gutierrez (IEEC/ICE-CSIC), M. Dennefeld (IAP), A. Gkini (Stockholm), N. Ihanec (Warsaw and ING), J. Anderson (ESO), T.-W. Chen (NCU), M. Gromadzki (Warsaw), C. Inserra (Cardiff), E. Kankare (Turku), M. Nicholl (QUB), O. Yaron (Weizmann), D. Young (QUB), report on behalf of the ePESSTO+ collaboration:

We observed the candidate counterpart of the short GRB 231117A (Laha et al., GCN Circ. 35071; Navaneeth et al., GCN Circ. 35072; Cattaneo et al., GCN Circ. 35075; Svinkin et al., Gin Circ. 35079; Cheung et al. GCN Circ. 35081; Dafcikova et al. GCN Circ. 35095) under the advanced Public ESO Spectroscopic Survey for Transient Objects (ePESSTO+; see Smartt et al. 2015, A&A, 579, 40; http://www.pessto.org). The observations were performed with the ESO New Technology Telescope (NTT) at La Silla equipped with the EFOSC2 instrument in spectroscopic mode, starting on 2023 Nov 18 at 00:22:34 UT (i.e. 21.3 hr after the burst) and using grism 13 (covering the wavelength range 3985-9315 AA). 

The 1.5" slit was oriented in order to cover both the optical afterglow and the host galaxy candidate positions (Yang et al., GCN Circ. 35083; Rastinejad et al., GCN 35087; Gompertz & Ackley, GCN 35088). However, the observations were carried out under poor seeing conditions (1.7") and in the acquisition image the two objects cannot be distinguished.

The spectrum shows prominebt emission features, which we identify as [O II], [O III] and Halpha at a common redshift z = 0.257, in agreement with the findings of Ahumada et al. (GCN Circ. 35093). No clear absorption features are detected.


GRB_name: GRB231117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35099
SUBJECT: GRB 231117A: Lowell Discovery Telescope Observations
DATE:    23/11/18 17:18:44 GMT
FROM:    Brendan O'Connor at Carnegie Mellon University <boconno2@andrew.cmu.edu>

I. Andreoni (JSI/UMD/NASA-GSFC), G. Srinivasaragavan (UMD), B. O'Connor (CMU), T. Ahumada (Caltech), S. B. Cenko (NASA-GSFC), J. Durbak (UMD), E. Hammerstein (UMD), N. Klingler (UMBC/NASA-GSFC), A. Kutyrev (NASA-GSFC), L. Singer (NASA-GSFC), S. Veilleux (UMD):

We report target of opportunity follow-up observations of GRB 231117A (Laha et al., GCN 35071; Navaneeth et al., GCN 35072; Beardmore et al., GCN3574; Cattaneo et al., GCN 35075; Svinkin et al., GCN 35079; Cheung et al., GCN 35081, Dafcikova et al., GCN 53095) with the Large Monolithic Imager (LMI) mounted at the Lowell Discovery Telescope (LDT) located in Flagstaff, AZ, under program M01 (PI: Andreoni).

Observations started on 2023-11-18 at 01:46 UT (~22.7 hr after the GRB trigger). We obtained sets of 4x150s exposures for each g-r-i-z filter. The candidate afterglow identified by Yang et al.; GCN 35083 (also detected by Rastinejad et al., GCN 35087; Gompertz et al., GCN 35088; Kumar et al., GCN 35089, Ahumada et al., GCN 35093; Rhodes et al., GCN 35097) is well detected. Preliminary photometry of the images, with contribution from the host galaxy included and not corrected for Galactic extinction, was measured as follows in the AB magnitude system:

g = 20.55 +/- 0.04 mag
r = 20.20 +/- 0.04 mag
i = 20.05 +/- 0.04 mag
z = 19.98 +/- 0.03 mag

We thank Ben Shafransky and the Lowell Observatory staff for their support.


GRB_name: GRB231118A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35100
SUBJECT: GRB 231118A: Fermi GBM Final Real-time Localization
DATE:    23/11/18 17:27:02 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 17:16:29 UT on 18 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231118A (trigger 722020594.832338 / 231118720).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 4.0, Dec = -48.2 (J2000 degrees, equivalent to J2000 00h 16m, -48d 12'), with a statistical uncertainty of 1.4 degrees.

The angle from the Fermi LAT boresight is 118.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231118720/quicklook/glg_skymap_all_bn231118720.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231118720/quicklook/glg_healpix_all_bn231118720.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231118720/quicklook/glg_lc_medres34_bn231118720.gif


GRB_name: GRB231118A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35101
SUBJECT: GRB 231118A: Swift detection of a burst
DATE:    23/11/18 17:31:56 GMT
FROM:    David Palmer at LANL <palmer@lanl.gov>


S. Laha (GSFC/UMBC), M. Ferro (INAF-OAB), C. Gronwall (PSU),
M. J. Moss (GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL),
T. M. Parsotan (GSFC/UMBC/CRESSTII), T. Sbarrato (INAF-OAB),
M. H. Siegel (PSU) and A. Tohuvavohu (U Toronto) report on behalf of
the Neil Gehrels Swift Observatory Team:

At 17:16:33 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 231118A (trigger=1197311).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 4.843, -48.035 which is 
   RA(J2000) = 00h 19m 22s
   Dec(J2000) = -48d 02' 07"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex
structure with a duration of about 15 sec.  The peak count rate
was ~11,000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

Due to a telemetry outage, XRT and UVOT data are not
immediately available and will be reported later. 

Burst Advocate for this burst is S. Laha (sib.laha AT gmail.com). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)


GRB_name: GRB231117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35102
SUBJECT: GRB 231117A: SOAR/Goodman imaging of the afterglow
DATE:    23/11/18 18:06:31 GMT
FROM:    Charles Kilpatrick at Northwestern U <ckilpatrick@northwestern.edu>

C. D. Kilpatrick (Northwestern), L. Santana (CBPF), R. Salinas (ULS), C. BriceÃ±o (NOIRLab/CTIO), C. Fuentes (PUC), C. Bom, A. Santos (CBPF) report on behalf of a larger collaboration:

â€œWe observed the putative host galaxy of GRB 231117A (Laha et al., GCN 30571, Navaneeth et al., GCN 35072, Cattaneo et al., GCN 35075, Svinkin et al., GCN 35079, Cheung et al., GCN 35081, Odeh et al., GCN 35084, D'Avanzo et al., GCN 35086, Rastinejad et al., GCN 35087, Gompertz et al., GCN 35088) with the Goodman High-Throughput Spectrograph mounted on the SOAR 4m telescope on Cerro Pachon, Chile.  We obtained 5x200s of imaging in r-band starting at 2023 Nov 18.03.

We detect a r=20.4+/-0.1 mag counterpart at the location of SDSS J220933.34+133119.5, consistent with the reported afterglow position reported by Yang et al. (GCN 35083) and subsequent detections of the putative afterglow (Rastinejad et al., GCN 35087, Gompertz & Ackley, GCN 35088, Kumar et al., GCN 35089, Andreoni et al., GCN 35099).  These data are on the AB magnitude system and not corrected for Galactic extinction, however we caution that these data are preliminary and there is uncertain contribution from the host galaxy in our aperture.  Additional SOAR follow up is planned.â€


GRB_name: GRB231118A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35103
SUBJECT: GRB 231118A: Skynet Optical Afterglow Discovery
DATE:    23/11/18 18:45:17 GMT
FROM:    Dylan Dutton at UNC Chapel Hill <ddutton59@gmail.com>

Dylan Dutton, Megan Dubay, Donovan Schlekat, Logan Selph, Daniel Reichart, Joshua Haislip, Vladimir Kouprianov, Daryl Janzen, Arie Verveer, John Kennewell, and Ruide Fu report on behalf of the Skynet Robotic Telescope Network at the University of North Carolina at Chapel Hill.

We observed the field of GRB 231118A with our 0.4m robotic telecope located in Meckering, Australia. The observation began at 17:19:11 UTC on Nov 18 2023, approximately 3 minutes after the trigger.

We obtained multiple expsoures in the B, V, R, and I filters. Exposure lengths were calculated using our automated exposure length scaling model.

We detected a bright object within the uncertainty radius of the Swift localization, at:
R.A. (J2000): 00:19:19.3583
Dec. (J2000): -48:02:24.923

We report the discovery photometry below.

ExpLen | Filter | Mag  | Date         | UTC
-----------------------------------------
3.034s | R      | 14.8 | Nov 18, 2023 | 17:19:30

Our images have been calibrated using stars from the APASS catalog.


GRB_name: GRB231118A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35104
SUBJECT: GRB 231118A: Swift-XRT position
DATE:    23/11/18 18:45:21 GMT
FROM:    K.L. Page at U Leicester <klp5@leicester.ac.uk>

K.L. Page and P.A. Evens (U. Leicester) report on behalf of the Swift-XRT
team:

Using promptly downlinked data we find an uncatalogued X-ray source
located at RA,Dec = 4.8314, -48.0390 which is equivalent to:

RA  (J2000) =  00 19 19.65
DEC (J2000) =  -48 02 20.8

with an uncertainty of 3.50 arcsec (radius, 90% containment).
This location is 31.4 arcsec from the BAT position, inside the BAT
error circle.

This circular is an official product of the Swift-XRT team.


GRB_name: GRB231117A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35105
SUBJECT: GRB 231117A: Kinder observations with Lulin observatory for AT 2023yba without fading in r band
DATE:    23/11/18 19:16:48 GMT
FROM:    Ting-Wan Chen at MPE <janet.chen@astro.su.se>

T.-W. Chen (NCUIA), S. Yang (HNAS), C.-S. Lin (NCUIA), S. Smartt (Oxford/QUB), M. Fraser (UCD), A.J. Levan (Radboud), M.-H. Lee, C.-C. Ngeow, Y.-C. Pan, H.-Y. Hsiao, W.-J. Hou, J.-K. Guo (NCUIA), Z.-N. Wang (HNAS), J. Gillanders (Oxford), M. Fulton, S. Srivastav, T. Moore, C. Angus, A. Aamer (QUB), and N. Tanvir (Leicester) report:

We observed the field of GRB 231117A (Laha et al., GCN 35071; Navaneeth et al., GCN 35072; Beardmore et al., GCN 35074; Cattaneo et al., GCN 35075; Svinkin et al., GCN 35079; Cheung et al., GCN 35081; Dafcikova et al. GCN 35095).

The afterglow candidate was initially identified in our previous report (Yang et al., GCN 35083) . Since it is a real astrophysical transient, but not yet confirmed as the afterglow, we registered it as AT2023yba (Chen et al., TNS 194096).

We used the 40cm SLT at Lulin Observatory, Taiwan to obtain r-band images of the field of GRB 231117A, as part of the Kinder collaboration (Chen et al., AstroNote 2021-92). The first SLT epoch of observations started at 10:51 UT on 18 of November 2023 (MJD = 60266.452), 1.32 days after the Swift trigger. The r-band images were combined from 21 frames with a 300-second exposure time for the r band, taken under seeing conditions of an average of 1".87 and at a median airmass of 1.16. Then we continuously conducted observations of i, g, and z-band images, commencing from MJD = 60266.552, under seeing conditions of an average of 1".94 and at a median airmass of 1.83.

We used the Kinder pipeline (Yang et al. A&A 646, A22) to measure the PSF photometry of AT 2023yba after template subtraction using the SDSS images. We obtained the following magnitudes and a 3-sigma detection limit (in the AB system):

r = 20.86 +/- 0.13 mag (exposure time of 300sec*21),
i = 20.94 +/- 0.17 mag (300sec*6),
g = 21.37 +/- 0.13 mag (300sec*6) and
z > 20.02 mag (300sec*6).

The given magnitudes derived based on calibrating against SDSS field stars and is not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V) = 0.06 mag in the direction of the burst (Schlafly & Finkbeiner 2011).

Since the various GCNs on this source have heterogeneous methods, we focus on comparing our own nightly template subtracted measurements. By comparing these data with measurements on MJD = 60265.435 (at the epoch of 7.39 hours after the Swift trigger), we found AT 2023yba has faded by more than 0.4 mag in g and i bands in one day, but no fading in the r band. No fading in r band was also noticed in Kumar et al. (GCN 35089) at the epoch of 10.56 hours. The redshift of the host galaxy, SDSS J220933.34+133119.5, has been spectroscopically confirmed at z = 0.257 (Ahumada et al., GCN 35093; Gonzalez-BaÃ±uelos et al., GCN 35098), placing this transient at absolute magnitude M_r = -19.6 mag.


GRB_name: GRB231118A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35106
SUBJECT: GRB 231118A: Enhanced Swift-XRT position
DATE:    23/11/18 20:12:11 GMT
FROM:    Phil Evans at U of Leicester <pae9@star.le.ac.uk>

P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 539 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 231118A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 4.83131, -48.03940 which is equivalent
to:

RA (J2000): 00h 19m 19.51s
Dec (J2000): -48d 02' 21.8"

with an uncertainty of 2.2 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.


GRB_name: GRB231118A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35108
SUBJECT: GRB 231118A: Continued Skynet Observations
DATE:    23/11/18 21:49:27 GMT
FROM:    Dylan Dutton at UNC Chapel Hill <ddutton59@gmail.com>

Dylan Dutton, Megan Dubay, Ruide Fu, Donovan Schlekat, Logan Selph, Daniel Reichart, Joshua Haislip, Vladimir Kouprianov, Daryl Janzen, Arie Verveer, and John Kennewell report on behalf of the Skynet Robotic Telescope Network at the University of North Carolina at Chapel Hill.

We continued to observe the afterglow of GRB 231118A located at RA=00:19:19.3583, Dec=-48:02:24.923 (GCN 35103, Dutton et al.) with our 0.4m robotic telecope located in Meckering, Australia. The observation began at 17:19:11 UTC on Nov 18 2023, approximately 3 minutes after the trigger, and continued for approximately 100 minutes, until 18:54:53 UTC. We obtained multiple expsoures in the B, V, R, and I filters.

During the first approximately 40 minutes of the observation, the afterglow faded very slowly, and irregularly, with an approximate temporal index between -0.2 and -0.1.

After 40 minutes, the afterglow faded much more quickly with an approximate temporal index between -2 and -1.5, which could be consistent with the non-detection from Global MASTER-Net (GCN 35107, Lipunov et al.).

Throughout the entire observation, the afterglow is very red, with an approximate spectral index between -2 and -1.5. This is likely due to source-frame dust.

We report the photometry of our most recent images below.

ExpLen  | Filter | Mag   | MagErr | Date         | UTC
-----------------------------------------------------------
110.95s | R      | 17.02 | 0.04   | Nov 18, 2023 | 18:52:55
89.47s  | I      | 16.65 | 0.07   | Nov 18, 2023 | 18:54:53

Our images have been calibrated using stars from the APASS catalog.


GRB_name: GRB231118A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35109
SUBJECT: GRB 231118A: MASTER OT observation
DATE:    23/11/18 22:10:51 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>


V.Lipunov (Lomonosov MSU), D.Buckley (SAAO),
A.Kuznetsov, D.Vlasenko, P.Balanutsa, K.Zhirkov, E.Gorbovskoy, Ya.Kechin, Yu.Tselik,
N.Tiurina, I.Gorbunov, V.Vladimirov, D.Zimnukhov, V.Senik, V.Topolev, A.Yudin,
A.Chasovnikov, D.Cheryasov, A.Sosnovskij, A.Pozdnyakov, M.Gulyaev (Lomonosov MSU,SAI,PhysicsDepartment),
O.A. Gres, N.M. Budnev (Irkutsk State University, API),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity)

MASTER Global robotic net (MASTER-Net:http://observ.pereplet.ru Lipunov etal.,2010,Advances in Astronomy,2010,30L)
started Fermi (GCN 35100) and
Swift (Evans et al. GCN 35101, GCN 35104, GCN 35106) GRB 231118A error box observation at 2023-11-18 20:19:50 UT by MASTER-SAAO (Lipunov et  al. GCN 35107).

There is optical counterpart MASTER OT J001919.45-480224.7
 with m_OT=19.2m+-0.2m at 2023-11-18 20:26:40 and next 5 expositions (automatic, unfiltered, mlim=19.5), at Skynet position (discovered by Dutton et al. GCN 35103, GCN 35108)

Observations started at 70deg.altitude.

Observation and reduction will be continued.


GRB_name: GRB231118A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35110
SUBJECT: GRB 231118A: LCOGT Optical Observations
DATE:    23/11/18 22:32:28 GMT
FROM:    Robert Strausbaugh at Eastern Illinois University <rstrausbaugh@eiu.edu>

R. Strausbaugh (Eastern Illinois University), A. Cucchiara (NASA) report on behalf of a larger collaboration:

We observed the Swift/Fermi GRB 231118A field (Fermi GBM Team, GCN 35100; Laha et al., GCN 35101)  with the LCOGT 1-meter Sinistro instrument at the South African Astronomical Observatory site, on November 18, from 21:20 to 21:52 UT (corresponding to 4.07 to 4.60 hours from the GRB trigger time) with the Bessel R and I filters.

We performed a series of 3x300s exposures in each band.  We detect an uncataloged source consistent with the Skynet afterglow candidate (Dutton et al., GCN 35103) in both bands.  This result is consistent with fading detected in continued Skynet observations (Dutton et al., GCN 35108) and MASTER observations (Lipunov, et al., GCN 35109)

The following magnitudes are calculated using the USNO-B1.0 catalog as reference:

R = 19.08 +/- 0.04
I = 18.67 +/- 0.03

These magnitudes are not corrected for galactic extinction.


GRB_name: GRB231118B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35111
SUBJECT: GRB 231118B: Fermi GBM Final Real-time Localization
DATE:    23/11/18 22:44:35 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 22:34:14 UT on 18 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231118B (trigger 722039659.86232 / 231118940).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 348.9, Dec = 33.6 (J2000 degrees, equivalent to J2000 23h 15m, 33d 36'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 83.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231118940/quicklook/glg_skymap_all_bn231118940.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231118940/quicklook/glg_healpix_all_bn231118940.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231118940/quicklook/glg_lc_medres34_bn231118940.gif


GRB_name: GRB231118B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35112
SUBJECT: GRB 231118B: BALROG localization (Fermi Trigger 722039659 / GRB 231118940)
DATE:    23/11/18 23:42:44 GMT
FROM:    Jochen Greiner at MPE <jcgrog@mpe.mpg.de>

T. Preis, B. Biltzinger, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
722039659 at 22:34:14 on 18 Nov. 2023 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).

The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 346.7+/-0.8 deg
Decl.(2000.0) = 33.9+/-1.2 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB231118940/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB231118940/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB231118940/json

                        


GRB_name: GRB231118A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35113
SUBJECT: GRB 231118A: Las Cumbres optical detection
DATE:    23/11/19 00:04:57 GMT
FROM:    Manisha Shrestha at University of Arizona <mshrestha1@arizona.edu>

M. Shrestha (Univ. of Arizona),  D. Sand (Univ. of Arizona), K. D. Alexander (Univ. of Arizona), J. Andrews (Gemini), J. Pearson (Univ. of Arizona), N. Smith (Univ. of Arizona), K. Bostroem (Univ. of Arizona) D. A. Howell (LCO/UCSB), C. McCully (LCO/UCSB), M. Newsome (LCO/UCSB), E Padilla Gonzalez (LCO/UCSB), C. Pellegrino (LCO/UCSB), G. Terreran (LCO/UCSB), J. Farah (LCO/UCSB) report on behalf of a wider Global Supernova Project collaboration:
 
We observed the field of GRB 231118A (Fermi GBM team GCN 34937, Swift GCN 34938) with the 1-m telescope, on 2023-11-18T22:30:11.370 UT (60266.937 MJD, ~5.3 hours after the trigger) using the Sinistro instrument in g, r, i bands. We detect the GRB with the following magnitude:
g = 19.81 +-0.09
r =  19.45 +-0.14
i =  19.44 +-0.19

Magnitudes were calculated with respect to ATLAS-REFCAT2 (Tonry et al. 2018, ApJ 867 105) catalog and are not corrected for galactic extinction. These values are consistent with other detections (Dutton et al., GCN 35103, Dutton et al., GCN 35108, Lipunov et al., GCN 35109, Strausbaugh et al., GCN 35110)


GRB_name: GRB231117A
Detection_method: VLA Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35114
SUBJECT: GRB 231117A: 10 GHz VLA detection
DATE:    23/11/19 03:49:13 GMT
FROM:    Genevieve Schroeder at Northwestern University <genevieveschroeder2023@u.northwestern.edu>

G. Schroeder (Northwestern), W. Fong, T. Laskar (Utah) report:

"We observed the position of the short GRB 231117A (Laha et al., GCN 35071,
Navaneeth et al., GCN 35072, Cattaneo et al., GCN 35075, Svinkin et al.,
GCN 35079, Cheung et al., GCN 35081) with the Karl G. Jansky Very Large
Array (VLA) under program 23A-296 (PI: Schroeder) beginning on 2023 Nov.
17.98 UT (0.85 days post-burst) for 0.75 hours at a mean frequency of 10
GHz.

We confirm the presence of a radio source consistent with the location of
the putative optical afterglow and host galaxy (Yang et al. GCN 35083,
Rastinejad et al., GCN 35087, Gompertz & Ackley, GCN 35088, Kumar et al.,
GCN 35089, Andreoni et al., GCN 35099, Kilpatrick et al., GCN 35102, Chen
et al. 35105). We measure a flux density of ~190 uJy, resulting in a radio
luminosity of ~4e29 erg/s/Hz, consistent with typical radio luminosities of
SGRB radio afterglows (Laskar et al. 2022).

Our measured flux density is somewhat fainter than the 9 GHz flux with ATCA
reported by Rhodes et al. (GCN 35097). While the ATCA observations occurred
at a slightly earlier mid-time of 0.54 days than our VLA observations, we
cannot make a strong statistically significant claim regarding fading
between the two observations at this time.

We thank the VLA staff for quickly approving and executing these
observations. Further observations are planned to assess the nature of the
radio source."
ReplyForward


GRB_name: GRB231115A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35115
SUBJECT: GRB 231115A: Upper limit from CALET Gamma-Ray Burst Monitor
DATE:    23/11/19 05:41:13 GMT
FROM:    Yuta Kawakubo at Louisiana State University <kawakubo1@lsu.edu>

Y. Kawakubo (LSU), A. Yoshida, T. Sakamoto, S. Sugita (AGU),
K. Yamaoka (Nagoya U), S. Nakahira (JAXA),
Y. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (Waseda U),
Y. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC),
M. L. Cherry (LSU), S. Ricciarini (U of Florence),
P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The CALET Gamma-ray Burst Monitor (CGBM) was operating at
the trigger time of the short GRB 231115A
T0 = 2023-11-15 15:36:21.20 UT (Fermi GCN: #35035, #35044;
Integral GCN: #35037; Glowbug GCN #35045; Insight-HXMT/HE GCN
#35060; Konus-Wind GCN #35062; Swift-BAT GCN #35065).

No CGBM onboard trigger occurred around T0. Based on the IBAS
localization, the incident angles to HXM and SGM are 79 degrees and
85 degrees, respectively (#35037). Based on the analysis of the light
curve data with 0.125 sec time resolution, we found a hint of the burst
emission around the trigger time in HXM2 and SGM data.  However, the
significance of 4.8 (HXM2) and 4.7 (SGM) sigma is below our detection
criterion to the CGBM data.

The five sigma upper limit of SGM for a 0.125 integration time is
3.0e-6 erg/cm^2/s (10 - 1000 keV), assuming a power-law with
an exponential cutoff (alpha = 0.5, Epeak = 580 keV, reference to
#35044) and the IBAS position.

The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at Waseda University.


GRB_name: GRB231118A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35116
SUBJECT: GRB 231118A: AstroSat CZTI detection
DATE:    23/11/19 05:42:15 GMT
FROM:    Gaurav Waratkar at IIT Bombay <gauravwaratkar@iitb.ac.in>

P. K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long-duration GRB 231118A which was also detected by Fermi-GBM (Fermi GBM team, GCN Circ. 35100), and Swift-BAT (Laha et al., GCN Circ. 35101).

The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2023-11-18 17:16:33.55 UTC. The measured peak count rate associated with the burst is 773 (+165, -131) counts/s above the background in the combined data of three quadrants (out of four), with a total of 885 (+229, -215) counts. The local mean background count rate was 237 (+5, -8) counts/s. Using cumulative rates, we measure a T90 of 3.9 (+1.6, -1.0) s.

The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-11-18 17:16:32.74 UTC. The measured peak count rate associated with the burst is 638 (+71, -77) counts/s above the background in the combined data of all quadrants, with a total of 1634 (+436, -460) counts. The local mean background count rate was 1222 (+9, -10) counts/s. We measure a T90 of 3.7 (+1.8, -1.3) s from the cumulative Veto light curve.

CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.

CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB231117A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35117
SUBJECT: GRB 231117A: GECAM-C detection
DATE:    23/11/19 06:27:53 GMT
FROM:    Wang-Chen Xue <wcxuemail@gmail.com>

Wang-Chen Xue, Shao-Lin Xiong and Chen-Wei Wang
report on behalf of the GECAM team:

GECAM-C was triggered on ground by a short burst, GRB 231117A at
2023-11-17T03:03:19.210 UTC (denoted as T0), which has been 
detected by Swift (GCN 35071), AstroSat (GCN 35072), AGILE (GCN 35075),
Konus-Wind (GCN 35079), Glowbug (GCN 35081), and GRBalpha (GCN 35095).

According to the ground data of GECAM-C, this burst mainly consists
of a short pulse with a duration (T90) of 0.59 +/- 0.04 sec (15-4000 keV).

The GECAM-C localization is consistent with the Swift/BAT localization
(GCN 35074) within the error.

The time-averaged spectrum of GECAM-C data from T0 to T0+1.3 s could be
adequately fit by a cut-off power-law with photon index alpha of -1.52 (-0.07, +0.09),
and peak energy Ep of 437 (-174, +556) keV. The corresponding burst fluence is
8.40 (-1.64, +2.70) * 10^-6 erg/cm^2 in 15-4000 keV.

We note that these results are preliminary and refined analysis will be reported later.

Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor
(GECAM) mission originally consists of two micro-satellites (GECAM-A and GECAM-B)
launched in Dec. 2020. As the third member of GECAM constellation, 
GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. 
GECAM mission is funded by the Chinese Academy of Sciences (CAS).


GRB_name: GRB231117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35118
SUBJECT: GRB 231117A: AKO Follow-Up Observation
DATE:    23/11/19 06:50:00 GMT
FROM:    Mohammad Odeh at Al Khatim Observatory M44 <mshodeh@gmail.com>

M. Odeh (Al-Khatim Observatory, AKO, operated by the International
Astronomical Center in Abu Dhabi, UAE) and N. Guessoum, D. Akl and I. Abdi
(American University of Sharjah, UAE) report:

As a follow-up to our first observation of GRB 231117A, performed on Nov.
17, 2023 (GCN 35084 <https://gcn.nasa.gov/circulars/35084>), we again
observed the field with our 0.36m f/7.7 robotic telescope, on Nov. 18,
starting at 15:50 UT using an (Ic) filter.

We again detected a faint object at the same location of the source SDSS
J220933.34+133119.5 (PS1 ID = 124223323889577032), which is listed in the
Pan-STARRS catalogue with imag = 21.5, and in the SDSS catalogue with imag
= 20.9. The coordinates of the detected object are: R.A. (2000) =
22:09:33.36, Dec. (2000) = +13:31:20.1, which is consistent with the
coordinates of the candidate optical source reported by Yang et al. (GCN
35083 <https://gcn.nasa.gov/circulars/35083>).

The following table summarizes the results of both nights using the Atlas
catalogue as a reference:
---------------------------------------------------------------------------
ObsTime (mid), T(Mid)â€“T(0), Exposure, Filter, Mag, RMS, Limiting Magnitude
---------------------------------------------------------------------------
2023-11-17 15:37:30Z, 12.6 h, 33x180s (stacked), Ic, 19.85, 0.20, 20.2
2023-11-18 15:50:06Z, 1.53 d, 40x180s (stacked), Ic, 19.78, 0.21, 20.4
---------------------------------------------------------------------------
The magnitudes are not corrected for galactic extinction.


GRB_name: GRB231117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35119
SUBJECT: GRB 231117A: MAAO 0.7-m telescope optical upper limit
DATE:    23/11/19 07:32:15 GMT
FROM:    Gu Lim at Pusan National University <lim9gu@gmail.com>

Lim, Gu (PNU); Park, Junyeong (PNU); Kim, Dohyeong (PNU); Paek, Gregory S. H. (SNU); Im, Myungshin (SNU); Park, Keunhong (MAAO); Choi, Changmin (MAAO); and GECKO Collaboration

We searched for the optical afterglow of GRB 231117A (S. Laha et al., GCN 35071) with a 0.7m telescope at Miryang Arirang Astronomical Observatory (MAAO), one of the facilities of the GW EM-Counterpart Korean Observatory (GECKO). We started the observation at 2023-11-17 10:04:30 UT and obtained 30 images of each 120s with I-band after 6.9 hours after the Swift detection (GCN 35071). No significant source is found within the updated Swift-XRT position (Beardmore et al. GCN 35074). The photometry is performed using a 2xFWHM diameter aperture. The flux is calibrated using the PanStarrs DR1 photometric catalog (AB system) as a reference. The depth is the limiting magnitude for a point source without the galactic extinction correction.

T0 = 2023-11-17T03:03:19 UT (Laha et al., GCN 35071)
Filter Mean_Date-obs(UT)    exptime(s)   T-T0(d)        FWHM(")    Depth_3sigma(AB)   Depth_5sigma(AB) zp       zper
--------------------------------------------------------------------------------------------------------------------------------------------------
I          2023-11-17T10:38:14  120x30           +0.32             3.41              >20.34                           >19.78                         25.99  0.02

Our detection limit is deeper than the report from MITSuME (Takei et al., GCN 35076).

Gravitational-wave EM Counterpart Korean Observatory (GECKO) is a network of 10+ 0.4m to 1m class telescopes worldwide.


GRB_name: GRB231117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35121
SUBJECT: GRB 231117A: Pan-STARRS1 follow-up confirms rapid fading
DATE:    23/11/19 11:22:19 GMT
FROM:    shubhamsrivastav@gmail.com

M. D. Fulton (QUB), S. Srivastav, S. J. Smartt (Oxford/QUB), J. H. Gillanders (Oxford), K. C. Chambers, M. E. Huber, A. S. B. Schultz (IfA, Hawaii), K. W. Smith, D. R. Young, M. Nicholl, M. McCollum, T. Moore, S. Sim, J. Weston, A. Aamer, C. R. Angus, X. Sheng (QUB), P. Ramsden (QUB/Birmingham), L. Shingles (GSI/QUB), J. Sommer (LMU/QUB), H. Stevance, L. Rhodes, S. Ramaiya, A. Andersson (Oxford), T. de Boer, J. Herman, J. Fairlamb, H. Gao, C. C. Lin, T. Lowe, E. Magnier, P. Minguez, I. A. Smith, R. J. Wainscoat (IfA, Univ. Hawaii), T.-W. Chen (NCU), A. Rest (STScI), C. Stubbs (Harvard) report:

We observed the field of GRB 231117A (Laha et al., GCN 35071; Navaneeth et al., GCN 35072; Beardmore et al., GCN 35074; Cattaneo et al., GCN 35075; Svinkin et al., GCN 35079; Cheung et al., GCN 35081; Dafcikova et al., GCN 35095) with Pan-STARRS1 (Chambers et al., 2016) on two nights in the grizy filters, with the exposures beginning on MJDs 60266.255617 and 60267.271553.

We apply the Pan-STARRS1 reference frames for image subtraction and in all exposures, the afterglow candidate identified by Yang et al. (GCN 35083) as AT2023yba is well detected in griz and marginally in y. We confirm a clear and significant fading in all bands in a comparison between the two nights of:

delta-g = 1.5 +/- 0.2
delta-r = 1.3 +/- 0.2
delta-i = 1.2 +/- 0.2
delta-z = 1.1 +/- 0.2

The latest r-band magnitude at 60267.282458 is r = 22.0 +/- 0.2. This confirms the fast-fading nature of the optical transient AT2023yba, indicating this optical source, discovered by Yang et al. (GCN 35083), is very likely the afterglow of GRB 231117A.

Operation of the Pan-STARRS1 and Pan-STARRS2 telescopes is primarily supported by the National Aeronautics and Space Administration under Grant No. NNX12AR65G and Grant No. NNX14AM74G issued through the SSO Near-Earth Object Observations Program. Data are processed at Queen's University Belfast enabled through the STFC grants ST/P000312/1 and ST/T000198/1.


GRB_name: GRB231118A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35123
SUBJECT: GRB 231118A: VLT/X-shooter redshift
DATE:    23/11/19 14:44:04 GMT
FROM:    Benjamin Schneider at MIT <bschn@mit.edu>

B. Schneider (MIT), A. Saccardi (GEPI, Observatoire de Paris), L. Izzo (INAF-Naples & DARK/NBI), A. J. Levan (Radboud), D. B. Malesani (DAWN/NBI), N. R. Tanvir (Univ. Leicester), G. Pugliese (Amsterdam), report on behalf of the Stargate collaboration:

We observed the field of the Swift/Fermi GRB 231118A (Fermi GBM Team, GCN 35100; Laha et al., GCN 35101) using the ESO VLT UT3 (Melipal) equipped with the X-shooter spectrograph. Our spectra cover the wavelength range 3000-21000 AA, and consist of 
4 exposures of 600s each. The observation mid-time is 01:23:787 UT on Nov 19 2023 (8.1 hr after the Fermi trigger).

In a 30s image taken with the acquisition camera on Nov 19 00:51:23 UT, we clearly detect the optical afterglow (Dutton et al., GCN 35103, GCN 35108; Lipunov et al., GCN 35109; Strausbaugh et al., GCN 35110; Shrestha et al, GCN 35113), for which we measure an AB magnitude r = 19.88 +/- 0.04 mag (calibrated against one nearby star from Legacy Survey).

In a preliminary reduction, we clearly detect a continuum over the entire wavelength range. From detection of multiple absorption features, which we interpret as being due to FeII, MnII, MgII, MgI and FeII*, ZnII, CrII, and CaII, we infer a common redshift of z = 0.8304.  We conclude this is the redshift of the burst. We also detect multiple emission lines (Halpha, Hbeta, OIII doublet) at a consistent redshift, which we interpret as being due to the GRB host galaxy. We also note the presence of additional absorption features likely due to multiple intervening systems.

We acknowledge expert support from the ESO staff in Paranal, in particular Thomas Rivinius and Matias Jones.


GRB_name: GRB231117A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35124
SUBJECT: GRB 231117A: OHP/T120 optical observations
DATE:    23/11/19 14:45:16 GMT
FROM:    Benjamin Schneider at MIT <bschn@mit.edu>

B. Schneider (MIT), C. Adami (LAM/Pytheas/AMU), D. Turpin (CEA Paris-Saclay), S. Basa (Pytheas/OHP/LAM), Jean Balcaen (Pytheas/OHP), E. Le Floc'h, F. SchÃ¼ssler (CEA Paris-Saclay), report on behalf of a larger collaboration:

We observed the field of the short GRB 231117A (Laha et al., GCN 35071; Navaneeth et al. GCN 35072; Cattaneo et al., GCN 35075; Svinkin et al., GCN 35079; Cheung et al., GCN 35081) and its afterglow candidate (Yang et al. GCN 35083; Rastinejad et al., GCN 35087; Gompertz et al., GCN 35088; Kumar et al., GCN 35089; Ahumada et al., GCN 35093; â€‹â€‹Rhodes et al., GCN 35097; Andreoni et al., GCN 35099; Kilpatrick et al., GCN 35102) using the T120cm telescope at Observatoire de Haute-Provence (France). A total of 11 exposures of 900 seconds were obtained in the r band at 19:52:31.680 UT on 2023-11-17, ~16.82h after the trigger.

In the combined frame, we measured a flux excess at the position of SDSS J220933.34+133119.5 compared to archive values. After subtracting the SDSS J220933.34+133119.5 galaxy using the Legacy Survey image, we clearly detect a source consistent with the afterglow candidate reported by Yang et al., GCN 35083.

The preliminary magnitude derived for that source is

r = 21.0 Â± 0.1 mag (AB)

The photometric calibration was performed using nearby stars from the PanSTARRS catalog and magnitudes are not corrected for Galactic extinction.

We acknowledge the Observatoire de Haute Provence staff for their excellent support.


GRB_name: GRB231118A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35126
SUBJECT: GRB 231118A: MeerLICHT afterglow detection
DATE:    23/11/19 15:33:03 GMT
FROM:    Simon de Wet at University of Cape Town <simdewet@gmail.com>

S. de Wet (UCT), P.J. Groot (Radboud/UCT/SAAO) and P.M. Vreeswijk (Radboud) report on behalf of the MeerLICHT consortium:

The 0.6 m wide-field MeerLICHT optical telescope located in Sutherland, South Africa, obtained a repeated series of 60 s exposures in the q,u,g,r,i,z bands of GRB 231118A following the Swift detection (Laha et al., GCN 35101). Observations started at 18:58:24 UT on 2023 November 18 (1.7 hours post-trigger) and continued until 21:46:37 UT, following the filter sequence quqgqrqiqz. 

We detect the optical afterglow first reported by Dutton et al. (GCN 35103) with the following AB magnitudes:

q = 17.65 +/- 0.05 at 18:58:56 UT
u = 18.39 +/- 0.20 at 19:00:35 UT
g = 18.03 +/- 0.09 at 19:04:08 UT
r = 17.40 +/- 0.12 at 19:07:43 UT
i = 17.24 +/- 0.11 at 19:28:53 UT
z = 17.72 +/- 0.17 at 19:50:19 UT

Our high cadence q-band observations show a power-law decline with temporal index of -1.63, consistent with the decay reported by Dutton et al. (GCN 35108).

MeerLICHT is built and run by a consortium consisting of Radboud University, the University of Cape Town, the South African Astronomical Observatory, the University of Oxford, the University of Manchester and the University of Amsterdam. 


GRB_name: GRB231118A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  35127
SUBJECT: GRB 231118A: Swift-XRT refined Analysis
DATE:    23/11/19 19:16:02 GMT
FROM:    Phil Evans at U of Leicester <pae9@star.le.ac.uk>

A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAR), T. Sbarrato (INAF-OAB),
S. Dichiara (PSU), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), K.L.
Page (U. Leicester), A.P. Beardmore (U. Leicester) and P.A. Evans
report on behalf of the Swift-XRT team:

We have analysed 5.0 ks of XRT data for GRB 231118A, from 86 s to 81.5
ks after the  BAT trigger. The data comprise 117 s in Windowed Timing
(WT) mode (the first 9 s were taken while Swift was slewing) with the
remainder in Photon Counting (PC) mode. 

The light curve can be modelled with an initial power-law decay with an
index of alpha=0.84 (+/-0.05), followed by a break at T+8184 s to an
alpha of 1.6 (+0.4, -0.3).

A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.36 (+0.14, -0.13). The
best-fitting absorption column is  8.6 (+3.4, -2.8) x 10^21 cm^-2, at a
redshift of 0.8304, in addition to the Galactic value of 1.9 x 10^20
cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index
of 1.51 (+0.13, -0.12) and a best-fitting absorption column of 8.9
(+2.5, -2.2) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10
keV flux conversion factor deduced from this spectrum  is 4.8 x 10^-11
(5.7 x 10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Galactic foreground: 1.9 x 10^20 cm^-2
Intrinsic column:    8.9 (+2.5, -2.2) x 10^21 cm^-2 at z=0.8304
Photon index:      1.51 (+0.13, -0.12)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01197311.

This circular is an official product of the Swift-XRT team.


