# GCN_circulars

GRB_name: GRB220210A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31580
SUBJECT: GRB 220210A: Fermi GBM detection
DATE:    22/02/11 20:51:36 GMT
FROM:    Christian Malacaria at NASA-MSFC/USRA  <cmalacaria@usra.edu>

C. Malacaria (USRA), P. Veres (UAH) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 23:56:38.37 UT on 10 February 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 220210A (trigger 666230203 / 220210998),
which was also detected by the Swift/BAT-GUANO (Tohuvavohu et al. 2022, GCN 31572),
Fermi-LAT (Longo et al. 2022, GCN 31576), and AGILE (Ursi et al. 2022, GCN 31575).
The Fermi GBM Final Real-time Localization (GCN 31568) is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 16 degrees.

The GBM light curve shows a main peak followed by fainter peaks
with a duration (T90) of about 43 s (10-1000 keV).
The time-averaged spectrum from T0-0.4 s to T0+2.7 s is
best fit by a power-law function with an exponential high-energy cutoff.
The power law index is -0.95 +/- 0.07 and the cutoff energy,
parameterized as Epeak, is 3530 +/- 986 keV.

The event fluence (10-1000 keV) in this time interval is
(4.9 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-0.192 s in the 10-1000 keV band
is 4.1 +/- 0.2 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: GRB220210A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31581
SUBJECT: GRB 220210A: 1.5m OSN optical upper limit
DATE:    22/02/11 22:54:43 GMT
FROM:    Youdong HU at IAA-CSIC  <huyoudong072@hotmail.com>

Y.-D. Hu, F. Aceituno, T.-R. Sun, A. J. Castro-Tirado, M. D. Caballero-Garcia, R. Sanchez-Ramirez and E. Fernandez-Garcia (IAA-CSIC), on behalf of a larger collaboration, report:

Following the detection of GRB 220210A by Fermi (Fermi Team, GCNC 31568), Swift (Tohuvavohu et al. GCNC 31572) and AGILE (Ursi et al. GCNC 31575), we triggered the 1.5m OSN telescope in Granada (Spain) starting on Feb 11 at 19:30 UT (i.e. ~19.6 h post burst). Five images covering the Swift/BAT-GUANO error region were taken in the I-band at high airmass. No optical afterglow is detected in the error box down to I=20.8 in the combined (5x300s) image, in agreement with the non-detections reported by Lipunov et al. (GCNC 31569) and Carrasco-Garcia et al. (GCNC 31574).

We thank the staff at OSN for their excellent support.


GRB_name: GRB220211A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31582
SUBJECT: GRB 220211A: Swift/BAT-GUANO detection outside the coded FOV (short)
DATE:    22/02/12 00:11:28 GMT
FROM:    Aaron Tohuvavohu at U Toronto  <aaron.tohu@gmail.com>

Aaron Tohuvavohu (U Toronto), Gayathri Raman (PSU), James DeLaunay
(UAlabama), Jamie A. Kennea (PSU), report:

Swift/BAT did not localize GRB 220211A onboard (T0: 2022-02-11T01:07:48
 UTC, Fermi/GBM GCN 31570).

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,
arXiv:2111.01769), detects the burst with a sqrt(TS) of 11.3 in a
0.128 s analysis time bin.
The duration of the burst is ~64 ms.

NITRATES results are consistent with a burst coming from outside the
coded FOV, with DeltaLLHOut of 3. An out of FOV origin is consistent
with the Fermi/GBM localization (GCN 31570).

See Section 9.1 and Figure 20 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: GRB220210A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31583
SUBJECT: GRB 220210A: Insight-HXMT/HE detection
DATE:    22/02/12 02:26:13 GMT
FROM:    Shenglun Xie at IHEP  <xiesl@ihep.ac.cn>

S. L. Xie, S. L. Xiong, X. B. Li, C. Cai, Q. Luo, S. Xiao, 
J. C. Liu, W. C. Xue, Q. B. Yi, C. Zhengï¼ŒY. Huang, C. K. Li, 
G. Li, J. Y. Liao, X. Y. Song, S. L. Xiong, C. Z. Liu, 
X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang, Y. F. Zhang, 
X. F. Lu, C. L. Zou (IHEP), Y. J. Jin, Z. Zhang (THU), 
T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, Y. Q. Zhang
M. Wu, Y. P. Xu, S. N. Zhang (IHEP), 
report on behalf of the Insight-HXMT team:

At 2022-02-10T23:56:38.550 (T0), Insight-HXMT/HE detected 
GRB 220210A (trigger ID: HEB220210997) in a routine search of the data, 
which also triggered Fermi/GBM (Fermi GBM Team, GCN #31568),
Swift/BAT (D'Ai A. et al., GCN #31572)

The Insight-HXMT/HE light curve mainly consists of single
pulse with a duration (T90) of 35.17 s measured from T0+2.60 s. 
The 1-ms peak rate, measured from T0-0.064 s, is 1992 cnts/sec. 
The total counts from this burst is 1726 counts. 
URL_LC: http://twiki.ihep.ac.cn/pub/HXMT/GRBList/HEB220210997_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 
of 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: GRB220211A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31584
SUBJECT: IPN triangulation of GRB 220211A (short)
DATE:    22/02/12 10:33:23 GMT
FROM:    Anna Ridnaia at Ioffe Institute  <ridnaia@mail.ioffe.ru>

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

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,

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

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

The short-duration GRB 220211A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 31570;
Swift/BAT-GUANO detection: Tohuvavohu et al., GCN Circ. 31582)
has been detected by Fermi (GBM trigger 666234473), INTEGRAL (SPI-ACS),
Konus-Wind, and Swift (BAT), so far, at about 4069 s UT (01:07:49).
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:
   208.379 (13h 53m 31s) +37.218 (+37d 13' 05")
  Corners:
   209.472 (13h 57m 53s) +52.187 (+52d 11' 14")
   209.036 (13h 56m 09s) +51.894 (+51d 53' 39")
   206.213 (13h 44m 51s) +22.653 (+22d 39' 12")
   206.450 (13h 45m 48s) +22.322 (+22d 19' 18")
 ---------------------------------------------
The error box area is 8 sq. deg, and its maximum
dimension is 29.6 deg (the minimum one is 16.1 arcmin).
The Sun distance was about 116 deg.

This box may be improved.

The IPN localization is consistent with, but reduces the area of, the
Fermi GBM Final Real-time position (GCN Circ. 31570) and BALROG
(https://grb.mpe.mpg.de/grb/GRB220211047/) localizations.

A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB220211_T04068/IPN/

The time history and spectrum will be given in forthcoming GCN Circulars.


GRB_name: GRB220210A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31586
SUBJECT: GRB 220210A: Mondy, AbAO and Terskol optical upper limits
DATE:    22/02/12 22:20:24 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

N. Pankov (HSE), A. Pozanenko (IKI), E. Klunko (ISZF),  R. Ya. 
Inasaridze (AbAO), I. Sokolov (INASAN, KIAM),  I. Izvekova (Institute of 
Physics of NAS, ICAMBR of NAS), A. Shein (INASAN), Y. Markus (Institute 
of Physics of NAS, ICAMBR NAS), Y. Markelov (KIAM),  G. Butenko (ICAMBR 
NAS), S. Belkin (IKI, HSE) report on behalf of GRB IKI:

We observed the field of Swift/BAT-GUANO localization (Tohuvavohu et 
al.,  GCN 31572) of GRB 220210A (Fermi GBM team, GCN 31568) with 
AZT-33IK telescope of Mondy observatory, AS-32 telescope of Abastumani 
observatory, and Zeiss-2000 telescope in R-filter. Within localization 
area (Tohuvavohu et al.,  GCN 31572) we do not detect evident candidate 
in comparison with SDSS DR12 catalogue. The object reported by BOOTES 
team (Carrasco-Garcia et al., GCN 31573) is clearly visible in all of 
our observations and do not show significant variability  with R= 20.17 
+/- 0.14 (0.54116 d),  R= 20.05 +/- 0.13 (0.72701 d), and R=20.14 +/- 
0.13 (0.77438 d). This highly reddened object visible in DDS-2 Infrared 
Survey (Carrasco-Garcia et al., GCN 31574) is also presented in SDSS 
DR12 as a star-like very red object with r=21.187.

Preliminary photometry of the field is following

Date UT start t-T0 Filter Exp. OT Err UL(3sigma) Telescope

2022-02-11 12:32:54 0.54116 R    23*120  n/d   n/d   22.7 AZT-33IK
2022-02-11 16:58:32 0.72701 R     50*60  n/d   n/d   21.9 AS-32 
2022-02-11 19:41:36 0.77438 R    35*180  n/d   n/d   22.2 Zeiss-2000

The photometry is based on the nearby USNO-B1.0 stars
RA DEC R2
RA DEC R2
345.7846139 61.8542256 14.69
345.7584140 61.8282804 17.76


GRB_name: GRB220214A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31588
SUBJECT: GRB 220214A: Fermi GBM Final Real-time Localization
DATE:    22/02/14 00:13:00 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 00:02:40 UT on 14 Feb 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220214A (trigger 666489765.60832 / 220214002).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 125.9, Dec = 16.7 (J2000 degrees, equivalent to J2000 08h 23m, 16d 41'), with a statistical uncertainty of 3.9 degrees.

The angle from the Fermi LAT boresight is 99.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220214002/quicklook/glg_skymap_all_bn220214002.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220214002/quicklook/glg_healpix_all_bn220214002.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220214002/quicklook/glg_lc_medres34_bn220214002.gif


GRB_name: GRB220211A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31590
SUBJECT: ZTF22aaajecp/AT2022cmc: Zwicky Transient Facility discovery of a fast and red optical transient
DATE:    22/02/14 18:47:06 GMT
FROM:    Igor Andreoni at JSI  <igor.andreoni@gmail.com>

Igor Andreoni (JSI), Michael Coughlin (UMN), Tomas Ahumada (UMD), Mansi
Kasliwal (Caltech), Daniel Perley (LJMU), Eric Burns (LSU), Mattia Bulla
(OKC), Brad Cenko (NASA/GSFC), Shreya Anand (Caltech), Erik Kool (OKC)


We report the discovery of the fast and red optical transient
ZTF22aaajecp/AT2022cmc with the Zwicky Transient Facility (ZTF, Bellm et
al. 2019, Graham et al. 2019) at coordinates:

RA = 13:34:43.20 (203.6800149d)
Dec = +33:13:00.44 (33.2167887d)

ZTF22aaajecp was first detected on 2022-02-11 10:42 UT at r=20.73 +- 0.3
mag. The last ZTF upper limit before the first detection was measured on
2022-01-21 09:54 UT. ZTF22aaajecp increased its luminosity to r=19.04 +-
0.16 mag in 23.2 hours, then it faded by 0.8 mag in the following 48 hours.
The latest detection of ZTF22aaajecp occurred on 2022-02-14 09:40 UT,
r=19.84 +- 0.19 mag.

The color of ZTF22aaajecp appears to be red, with g-r~0.25 mag and g-i~0.5
mag at the observed peak on 2022-02-12. The Galactic extinction on the line
of sight is small, with E(B-V)=0.01 mag (Planck Collaboration et al.,
2014). The source is located at a high Galactic latitude of b=78.85 deg.

ZTF22aaajecp does not have any cataloged underlying source in deep Legacy
Survey DR9 images. The fast evolution and red color suggest that
ZTF22aaajecp could be a gamma-ray burst afterglow, but a spectroscopic
confirmation is required to determine the nature of the transient.

ZTF22aaajecp is spatially and temporally consistent with the Fermi-GBM
short GRB 220211A (GBM trigger 666234473); however, it is located several
degrees outside the IPN localization region for this event (Ridnaia et al.
2022; GCN 31584).

Follow-up observations are strongly encouraged.


ZTF22aaajecp was discovered by the ''ZTF Realtime Search and Triggering''
project (ZTFReST; Andreoni & Coughlin et al., 2021) within the ZTF
Collaboration.

Based on observations obtained with the Samuel Oschin Telescope 48-inch and
the 60-inch Telescope at the Palomar Observatory as part of the Zwicky
Transient Facility project. ZTF is supported by the National Science
Foundation under Grant No. AST-2034437 and a collaboration including
Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center
at Stockholm University, the University of Maryland, Deutsches
Elektronen-Synchrotron and Humboldt University, the TANGO Consortium of
Taiwan, the University of Wisconsin at Milwaukee, Trinity College Dublin,
Lawrence Livermore National Laboratories, and IN2P3, France. Operations are
conducted by COO, IPAC, and UW.


GRB_name: GRB220211A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31591
SUBJECT: GRB 220211A: Fermi GBM observation
DATE:    22/02/14 19:57:14 GMT
FROM:    Peter Veres at UAH  <veresp@gmail.com>

P. Veres and C. Meegan (both UAH)
report on behalf of the Fermi GBM Team:

"At 01:07:48.88 UT on 11 February 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 220211A (trigger 666234473 / 220211047),
which was also detected by the Swift/BAT-GUANO (Tohuvavohu et al. GCN 31852).

The Fermi GBM Final Real-time Localization was reported in GCN 31570.

The GBM light curve consists of a single short pulse
with a duration (T90) of about 0.4 s (50-300 keV).
The time-averaged spectrum from T0-64 ms to T0+128 ms is
adequately fit by a simple power law function with index -1.42 +/- 0.07.

The event fluence (10-1000 keV) in this time interval is
(1.28 +/- 0.19)E-6 erg/cm^2. The 64 ms peak photon flux measured
starting from T0-64 ms in the 10-1000 keV band
is 12.8 +/- 2.7 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: GRB211023A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31596
SUBJECT: GRB 211023A: evidence of supernova in LBT spectra
DATE:    22/02/16 08:49:19 GMT
FROM:    Andrea Rossi at INAF  <andrea.rossi@inaf.it>

A. Rossi, E. Pian, E. Palazzi (INAF-OAS), A. Melandri (INAF-OAB), on 
behalf of the CIBO collaboration, B. Rothberg (LBTO/GMU), A. Pozanenko, 
S. Belkin (IKI), and D. A. Kann (HETH/IAA-CSIC) report :

We report the results of the photometric and spectroscopic follow-up 
observations of GRB 211023A (Fermi GBM team, GCN 30958; Di Lalla et al., 
GCN 30961; Lesage et al, GCN 30965; Ursi et al, GCN 30969; Poolakkil, 
GCN 30998; Ridnaia et al., GCN 31022) at z = 0.390 (Pozanenko et al., 
GCN 31053) obtained with the Multi-Object Double Spectrographs (MODS) 
instrument mounted on the 2x8.4-m LBT telescope (Mt. Graham, AZ, USA). 
Data were obtained at ~12 UT on 2021-11-05, ~13 days (i.e. 9 rest-frame 
days) after the burst trigger.

Spectroscopy of the source was obtained for a total of 4x900 s, covering 
the wavelength range 3200-10000 AA. The spectrum has been corrected for 
Galactic extinction (A_V = 0.45 mag). The contribution of the host 
galaxy was removed via a galaxy template matching the emission line 
fluxes. The low S/N spectrum shows features similar to those exhibited 
by XRF-associated SN2006aj at a similar phase (Mazzali et al. 2006, 
Nature, 442, 1018). This confirms the bump observed by Belkin et al. 
(GCN 31098), as due to the emerging contribution of the SN.

We acknowledge the excellent support from the LBTO in particular O. Kuhn 
and S. Allanson, and from the LBT-INAF staff, particularly F. Cusano, S. 
Paiano, and E. Marini in obtaining these observations.


GRB_name: GRB220209A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31598
SUBJECT: IPN triangulation of GRB 220209A
DATE:    22/02/16 13:28:54 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 team,

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, and C. Wilson-Hodge
on behalf of the Fermi GBM team,

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB 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 220209A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 31561;
Lesage eat al., GCN Circ. 31565;
AGILE-MCAL detection: Ursi et al., GCN Circ. 31563;
GECAM detection: Zhang et al., GCN Circ. 31564;
Fermi-LAT detection: Pesce-Rollins et al., GCN Circ. 31577)
was detected by Fermi (GBM trigger 666140455), GECAM-B, AGILE (MCAL),
Konus-Wind, INTEGRAL (SPI-ACS), and BepiColombo (MGNS)
at about 82850 s UT (23:00:50).

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   351.998 (23h 28m 00s) +69.556 (+69d 33' 22")
  Corners:
    19.772 (01h 19m 05s) +60.497 (+60d 29' 49")
    18.826 (01h 15m 18s) +61.426 (+61d 25' 34")
   310.634 (20h 42m 32s) +70.589 (+70d 35' 21")
   313.447 (20h 53m 47s) +70.575 (+70d 34' 31")
  ---------------------------------------------
The error box area is 7.1 sq. deg, and its maximum
dimension is 28.4 deg (the minimum one is 15.5 arcmin).
The Sun distance was 85 deg.

This box may be improved.

The IPN localization is consistent with, but reduces the area of, the
Fermi-GBM final position (GCN Circ. 31561) and the BALROG position
(https://grb.mpe.mpg.de/grb/GRB220209959/) localizations.

The distance between the center of the Fermi (LAT) position (GCN 31577) 
and the IPN error box is 3.3 deg.

A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB220209_T82859/IPN/

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


GRB_name: GRB220211A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31599
SUBJECT: Konus-Wind detection of GRB 220211A
DATE:    22/02/16 18:38:57 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, D. Frederiks, A.Lysenko, A. Ridnaia,
A. Tsvetkova,  M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:

The short-duration GRB 220211A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 31570;
Veres and Meegan GCN Circ. 31591;
Swift/BAT-GUANO detection: Tohuvavohu et al., GCN Circ. 31582;
IPN triangulation: Ridnaia et al., GCN Circ. 31584)
triggered Konus-Wind (KW) at T0=4070.727 s UT (01:07:50.727).

The burst light curve shows a single pulse with
the total duration of ~54 ms (20-1500 keV).

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB220211_T04070/

As observed by Konus-Wind, the burst had
a fluence of 3.86(-0.53,+0.82)x10^-7 erg/cm^2 and
a 16-ms peak energy flux, measured from T0-0.040 s,
of 9.6(-2.1,+2.6)x10^-6 erg/cm^2/s
(both in the 20 keV - 10 MeV energy range).

Since the main fraction of the burst emission was detected
before the trigger, the spectral analysis was performed using
the KW 3-channel light curve data.

Modelling the time-integrated spectrum of the burst
(measured from T0-0.050 s to T0+0.004 s)
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep),
yields alpha = 0.77(-0.62,+1.32) and Ep = 413(-74,+88) keV.

All the quoted errors are estimated at the 68% confidence level.
All the presented results are preliminary.


GRB_name: GRB220211A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31600
SUBJECT: GRB 220211A: MASTER optical observations of ZTF22aaajecp/AT2022cmc
DATE:    22/02/16 22:39:20 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, A.Kuznetsov, P.Balanutsa, A.Chasovnikov, K.Zhirkov, O.Gress,
N.Tiurina, G.Antipov, E.Gorbovskoy, D. Vlasenko, V.Senik, Ya.Kechin, V.Topolev (Lomonosov MSU,SAI,PhysicsDepartment),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
D. Buckley (South African Astronomical Observatory),
N.M. Budnev (Irkutsk State University, API),
C.Francile, R. Podesta, F. Podesta (OAFA),
L. Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J. Martinez, A.R.Corella, L.H.Rodriguez (INAOE, OAGH),
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 et al.,2010,Advances in Astronomy,2010,30L)
started inspect of Fermi short GRB 200211A (Ttrigger=2022-02-11 01:07:48UT, GCN 31570 https://gcn.gsfc.nasa.gov/other/220211A.gcn3)
33 sec after notice time (64 sec after trigger time) at 2022-02-11 01:08:53 UT
and observed it at MASTER-IAC, -Tavrida, -Amur, -Kislovodsk, 
-SAAO, -OAGH, see cover map in Lipunov et al. GCN 31571
https://master.sai.msu.ru/site/master2/observ.php?id=1878703 )

ZTF (Andreoni  et al. GCN31590) discovered new OT at
R.A.,Dec.=13:34:43.20,+33:13:00.44 (ZTF22aaajecp/AT2022cmc) on 2022-02-11 10:42 UT

We are analyzing 1864 MASTER database images of these coordinates since 2006y up to now.

Preliminary results of OT detections (unfiltered,calibrated by Gaia) are the following:
Date, m_OT
2022-02-13.03UT 19.4 
2017-11-14.85UT 17.8 
2014-03-27.68UT 19.0

The analysis will be continued.
Additional observations are planned.


GRB_name: GRB220209A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31604
SUBJECT: Konus-Wind detection of GRB 220209A
DATE:    22/02/18 17:54:23 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, D. Frederiks, M. Ulanov, A. Tsvetkova,
A. Lysenko, A. Ridnaia, and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration GRB 220209A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 31561;
Lesage eat al., GCN Circ. 31565;
AGILE-MCAL detection: Ursi et al., GCN Circ. 31563;
GECAM detection: Zhang et al., GCN Circ. 31564;
Fermi-LAT detection: Pesce-Rollins et al., GCN Circ. 31577;
IPN triangulation: Kozyrev et al., GCN Circ. 31598)
triggered Konus-Wind at T0=82859.23 s UT (23:00:59.230).

The burst light curve shows two emission episodes.
The first one, lasting from ~T0-12 s to ~T0+98 s, and
the second episode, from ~T0+147 s to ~T0+260 s.
The total burst duration was ~272 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/GRB220209_T82859/

As observed by Konus-Wind, the burst
had a fluence of 1.86(-0.32,+0.42)x10^-4 erg/cm2,
and a 64-ms peak flux, measured from T0+1.312 s,
of 1.12(-0.28,+0.29)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+218.624 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 = -0.83(-0.19,+0.60),
the high energy photon index beta = -1.81(-0.21,+0.16),
the peak energy Ep = 320(-162,+162) keV
(chi2 = 101/86 dof).

The spectrum near the maximum count rate
(measured from T0 to T0+7.936 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 = -0.89(-0.05,+0.06),
the high energy photon index beta = -3.17(-6.83,+0.89),
the peak energy Ep = 1675(-288,+289) keV
(chi2 = 96/86 dof).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB220211A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31606
SUBJECT: GRB 220211A: redshift lower limit estimating
DATE:    22/02/18 22:04:09 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 analysed GRB 220211A (The Fermi GBM team, GCN 31570; Tohuvavohu et 
al., GCN 31582; Ridnaia et al., GCN 31584; Svinkin et al., GCN 31599) 
using publicly available data of GBM/Fermi. We estimate the duration in 
7 - 850 keV energy band T_90 = 0.11 +/- 0.02 s. We performed spectral 
analysis in a time interval of (-0.05, 0.05) s, the best fit is obtained 
for CPL model with following parameters: E_p = 924 (-210, +317) keV, 
alpha = -0.50 +/- 0.25. The fluence of F = (5.8 +/- 0.5)E-7 erg/cm**2 is 
obtained in 10 - 1000 keV energy band.
Using T_90,i - EH diagram [1,2] we classify the burst as type I (short) 
and find the minimal possible redshift value of z  = 0.13 and the most 
probable value of the redshift z = 0.53.

The T_90,i - EH diagram can be found in
http://grb.rssi.ru/GRB220211A/GRB220211A_EHD.png

The burst could also be classified as SGR Giant flare, placed at 
distance of D_L = 8.7 Mpc.

[1] - Minaev et al., MNRAS, 492, 1919, 2020
[2] - Minaev et al., Astronomy Letters, 46, 9, 573, 2020


GRB_name: GRB220218A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31608
SUBJECT: GRB 220218A: Swift detection of a burst
DATE:    22/02/18 22:49:12 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

V. D'Elia (SSDC & INAF-OAR), S. Dichiara (PSU), J.D. Gropp (PSU),
N. J. Klingler (GSFC/UMBC/CRESSTII), A. Y. Lien (U Tampa),
F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL),
T. M. Parsotan (GSFC/UMBC/CRESSTII), M. H. Siegel (PSU) and
A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift
Observatory Team:

At 22:28:59 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 220218A (trigger=1093860).  Swift did not slew to the
burst location. 
The BAT on-board calculated location is 
RA, Dec 133.830, +31.984 which is 
   RA(J2000) = 08h 55m 19s
   Dec(J2000) = +31d 59' 02"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve for this image trigger
shows some variation on a multi-minute timescale following the
trigger, but further analysis with the downlinked data is required
to determine whether it is due to the GRB source. 

Swift is currently restarting after a reaction wheel failure, so
automatic slews to GRBs are turned off.  Therefore there will be
no XRT or UVOT observations at 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: GRB220219A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31609
SUBJECT: GRB 220219A: Fermi GBM Final Real-time Localization
DATE:    22/02/19 11:32:48 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 11:21:34 UT on 19 Feb 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220219A (trigger 666962499.096148 / 220219473).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 41.6, Dec = 9.0 (J2000 degrees, equivalent to J2000 02h 46m, 9d 00'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 79.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220219473/quicklook/glg_skymap_all_bn220219473.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220219473/quicklook/glg_healpix_all_bn220219473.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220219473/quicklook/glg_lc_medres34_bn220219473.gif


GRB_name: GRB220219A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31610
SUBJECT: GRB 220219A: BALROG localization (Fermi Trigger  / GRB 220219473)
DATE:    22/02/19 12:16:28 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

F. Kunzweiler, B. Biltzinger, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
 at 11:21:34 on 19 Feb. 2022 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) = 37.8+/-0.7 deg
Decl.(2000.0) = 17.0+/-1.1 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB220219473/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB220219473/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB220219473/json

                        


GRB_name: GRB220219A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31611
SUBJECT: GRB 220219A: AGILE/MCAL detection
DATE:    22/02/19 14:20:46 GMT
FROM:    Alessandro Ursi at INAF/IAPS  <alessandro.ursi@gmail.com>

A. Ursi (INAF/IAPS), M. Pilia (INAF/OA-Cagliari), M. Tavani (INAF/IAPS, and
Univ. Roma Tor Vergata), A. Argan, M. Cardillo, C. Casentini, Y.
Evangelista, L. Foffano, E. Menegoni, G. Piano (INAF/IAPS), F. Lucarelli,
C. Pittori, F. Verrecchia (SSDC, and INAF/OAR), A. Bulgarelli, V. Fioretti,
F. Fuschino, N. Parmiggiani (INAF/OAS-Bologna), M. Marisaldi
(INAF/OAS-Bologna, and Bergen University), A. Trois (INAF/OA-Cagliari), I.
Donnarumma (ASI), F. Longo (Univ. Trieste and INFN Trieste), A. Giuliani
(INAF/IASF-Mi), report on behalf of the AGILE Team:

The AGILE Mini-CALorimeter (MCAL) detected the GRB 220219A T0 = 2022-02-19
11:21:35.02 +/- 0.01 s (UTC), reported by Fermi GBM (GCN #31609).

The event lasted about 9.5 s and released a total number of 7450 counts in
the MCAL detector (in the 0.4-100 MeV energy range), above an average
background rate of 597 Hz. The MCAL light curve can be found at
http://www.agilescienceapp.it/notices/077070_GRB_MCAL_572354495.021853.png
. The time-integrated spectrum of the burst, from T0-3.0 s to T0+6.5 s, can
be fitted in the energy range 0.4-10 MeV with a power-law with ph.ind. =
-2.83 (-0.24,+0.28), resulting in a reduced chi-squared of 0.78 (48 d.o.f.)
and a fluence of 1.26e-05 erg/cm^2 (90% confidence level), in the same
energy range.

The burst is also clearly visible in the AGILE scientific ratemeters of the
MiniCALorimeter (MCAL; 0.4-100 MeV), and AntiCoincidence (AC; 50-200 keV)
detectors. The event lasted about 9 s and it released a total number of
13810 counts in the MCAL detector (above a background rate of 1210 Hz), and
33110 counts in the AC detector (above a background rate of 3370 Hz). The
AGILE ratemeter light curves can be found at
http://www.agilescienceapp.it/notices/GRB220219A_AGILE_RM.png . At the T0,
the event was 140 deg off-axis.

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.
Automatic MCAL GRB alert Notices can be found at:
https://gcn.gsfc.nasa.gov/agile_mcal.html.


GRB_name: GRB220218A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31613
SUBJECT: GRB 220218A: BOOTES-5/JGT optical upper limit
DATE:    22/02/19 20:09:42 GMT
FROM:    Youdong HU at IAA-CSIC  <huyoudong072@hotmail.com>

Y.-D. Hu, T.-R. Sun, E. Fernandez-Garcia, A. J. Castro-Tirado, M.D. Caballero-Garcia and R. Sanchez-Ramirez (IAA-CSIC), D. Hiriart and W. H. Lee (UNAM), C. J. Perez del Pulgar and I. Carrasco (UMA), I. H. Park (SKKU) on behalf of a larger collaboration, report:

Following the detection of GRB 220218A by Swift (D'Elia et al. GCNC 31608), the BOOTES-2/TELMA 0.6m telescope automatically started to observe the GRB localization within 2 min after trigger at the BOOTES-2 station at IHSM La Mayora (Algarrobo Costa, Spain). But due to bad weather, no useful early images were obtained. Later on, the BOOTES-5/JGT 0.6m robotic telescope at Observatorio Astronomico Nacional in San Pedro Martir (Mexico) responded to this burst starting on Feb 19 at 02:53 UT (~4.4 hours after trigger) right after the twilight. In the co-added image (23 x 60 s exposures in the clear filter), no optical afterglow is detected within the Swift/BAT error region (D'Elia et al. GCNC 31608) down to 20.5 mag. This non-detection is consistent with the MASTER observation (Lipunov et al. GCNC 31607).

We thank the staff at La Mayora and Observatorio Astronomico Nacional in San Pedro Martir for their excellent support.


GRB_name: GRB220219A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31621
SUBJECT: IPN triangulation of GRB 220219A
DATE:    22/02/21 16:12:59 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 HEND/Mars-Odyssey team,

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

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM 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 220219A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 31609;
BALROG localization: Kunzweiler et al.,  GCN Circ. 31610;
AGILE-MCAL detection: Ursi et al., GCN Circ. 31611)
has been detected by Fermi (GBM trigger 666962499), AGILE (MCAL),
Konus-Wind, and Mars-Odyssey (HEND), so far,
at about 40894 s UT (11:21:34).

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
    42.243 (02h 48m 58s) +10.588 (+10d 35' 17")
  Corners:
    43.946 (02h 55m 47s)  +6.216 ( +6d 12' 57")
    39.857 (02h 39m 26s) +17.180 (+17d 10' 49")
    39.457 (02h 37m 50s) +18.548 (+18d 32' 54")
    43.844 (02h 55m 23s)  +6.598 ( +6d 35' 54")
  ---------------------------------------------
The error box area is 2243 sq. arcmin, and its maximum
dimension is 13.1 deg (the minimum one is 3.1 arcmin).
The Sun distance was 72 deg.

This box may be improved.

The IPN localization is consistent with, but reduces the area of, the
Fermi GBM Final Real-time position (GCN Circ. 31609) and BALROG
(GCN 31610) localizations.

A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB220219_T40894/IPN/

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


GRB_name: GRB220219A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31622
SUBJECT: Konus-Wind observation of GRB 220219A
DATE:    22/02/21 17:12:32 GMT
FROM:    Anastasia Tsvetkova at Ioffe Institute  <tsvetkova@mail.ioffe.ru>

A. Tsvetkova, D. Frederiks, A. Lysenko, A. Ridnaia, D. Svinkin,
M. Ulanov, and T. Cline on behalf of the Konus-Wind team, report:

The long-duration GRB 220219A
(Fermi-GBM detection: The Fermi GBM team, GCN 31609;
AGILE/MCAL detection: Ursi at al., GCN31611;
IPN triangulation: Kozyrev et al., GCN 31621)
triggered Konus-Wind at T0=40894.695 s UT (11:21:34.695).

The burst light curve shows a multi-peaked structure
which starts at ~T0-0.4 s and has a total duration of~76.6 s.
The emission is seen up to ~15 MeV.

As observed by Konus-Wind, the burst
had a fluence of 5.75(-2.01,+1.80)x10^-5 erg/cm2,
and a 64-ms peak energy flux, measured from T0+3.792 s,
of 1.08(-0.21,+0.21)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst
(measured from T0 to T0+80.384 s)
is best fit in the 20 keV - 15 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -1.01(-0.39,+0.52),
the high energy photon index beta = -1.86(-1.11,+0.20),
the peak energy Ep = 379(-155,+830) keV,
chi2 = 93/97 dof.

The spectrum near the peak count rate
(measured from T0 to T0+6.656 s)
is best fit in the 20 keV - 15 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -1.03(-0.10,+0.11),
and Ep = 480(-57,+73) keV (chi2 = 97/98 dof).
Fitting by the GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index:
beta < -2.29 (chi2 = 96.1/97 dof).

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB220219_T40894/

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB220219B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31624
SUBJECT: IPN triangulation of GRB 220219B (consistent with ZTF22aabjpxh/AT2022cva)
DATE:    22/02/21 18:38:56 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

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

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

The long-duration GRB 220219B
has been detected by Konus-Wind (KW) and Swift (BAT), so far,
at about 34045 s UT (09:27:25).
The burst was outside the coded field of view of the BAT.

We have triangulated it to a Konus-BAT annulus centered at
RA(2000)=314.433 deg (20h 57m 44s) Dec(2000)=-14.987 deg (-14d 59' 15"),
whose radius is 83.789 +/- 1.439 deg (3 sigma).

This localization may be improved.

The position of the optical transient ZTF22aabjpxh/AT2022cva
(Ho et al., GCN Circ. 31619) is inside the annulus at 0.46 deg
from its center line. The OT position is consistent with the Swift-BAT 
detection, Fermi-GBM non-detection, and the KW ecliptic latitude response.

The positional and temporal coincidence of this burst with the OT 
supports the conclusion that the OT is the GRB counterpart.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB220219_T34045/IPN

The time history and spectrum will be given in forthcoming GCN Circulars.


GRB_name: GRB220211A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31626
SUBJECT: ZTF22aaajecb/AT 2022cmc: CAHA 2.2m/CAFOS detection, luminous transient
DATE:    22/02/21 21:16:30 GMT
FROM:    Alexander Kann at IAA-CSIC  <kann@iaa.es>

D. A. Kann (HETH/IAA-CSIC), A. de Ugarte Postigo (Obs. Cote d'Azur), C. 
C. Thoene (HETH/ASU CAS Ondrejov), M. Blazek (HETH), J. F. Agui 
Fernandez (HETH/IAA-CSIC), I. Vico, and A. Guijarro (both CAHA) report:

We observed the red ZTF transient ZTF22aaajecp/AT 2022cmc (Andreoni et 
al., GCN #31590), likely a GRB afterglow at z = 1.193 (Tanvir et al., 
GCN #31602; Lundquist et al., GCN #31612) with CAFOS, mounted on the 
2.2m telescope, at the Calar Alto Observatory (Almeria, Spain). The 
observation started at 04:54:04 UT on 18 February 2022 (6.76 days after 
the first ZTF detection) and consisted of 12 x 120 s integrations in the 
r' and i' bands, each. Observations were hampered by the full Moon, but 
otherwise conditions were very good (1".3 seeing, very good 
transparency). The transient is clearly detected in each of the stacked 
images.

Compared to a nearby Pan-STARRS comparison star, we measure r' = 21.12 
+/- 0.03 mag (AB) 6.772 days after first detection.

Gathering data from other GCNs (Andreoni et al., GCN #31590; Lipunov et 
al., GCN #31600; Kumar et al., GCN #31597; Pankov et al., GCNs #31593, 
#31625; Perley, GCN #31594), and assuming a GRB time one hour before the 
first detection (note the exact choice of time has little influence on 
the late decay slope), we find the transient is described by an 
achromatic decay with slope alpha = 1.05 +/- 0.05. The SED is described, 
similar to the result Perley (GCN #31594) found, by a simple power-law 
with slope beta = 1.29 +/- 0.22. This is slightly steeper than usual for 
synchrotron radiation from a typical GRB afterglow, indicating some 
extra extinction may play a role, as might be expected from the high 
X-ray column density found by NICER (Pasham et al., GCN #31601).

Using the known redshift and the spectral slope, we shift the afterglow 
into the z = 1 frame (following Kann, Klose & Zeh 2006, ApJ, 641, 993). 
We find that at 6.2 days (z = 1 frame), this transient is among the ten 
most luminous GRB afterglows, yielding further evidence that it itself 
is a bona fide GRB afterglow. The long rise indicates an off-axis 
origin, and the luminous afterglow makes it likely the initial GRB was 
very energetic. So far no viable candidates have been reported by the 
IPN (it is not positionally coincident with the short GRB 220211A, 
Andreoni et al., GCN #31590; also we note a short GRB at such a high 
redshift would not be expected to have such a luminous afterglow), 
leading to the conclusion that the off-axis angle was large enough to 
strongly suppress the prompt emission - a true orphan afterglow.


GRB_name: GRB220219B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31628
SUBJECT: ZTF22aabjpxh/AT2022cva: Assy optical observations
DATE:    22/02/22 00:16:49 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

V. Kim (FAI, HSE), A. Pozanenko (IKI),  M. Krugov (FAI), I. Reva (FAI), 
N. Pankov (HSE, IKI),  S. Belkin (IKI) report on behalf of GRB IKI FuN:

We observed ZTF22aabjpxh/AT2022cva transient (Ho et al., GCN 31619) what 
is considered the likely afterglow of GRB 220219B (Ho et al., GCN 31619; 
Svinkin et al., GCN 31624) with AZT-20 telescope of Assy-Turgen 
observatory starting on 2022-02-21 (UT) 19:44:30.

We clearly detect the SDSS galaxy at photo_z = 0.248 (Ho et al., GCN 
31619). Due to non-optimal seeing (FWHM of about 2.4") we could not 
discriminate the afterglow source from the galaxy. We use aperture 
photometry and preliminary photometry (AB) of a source (afterglow+host 
galaxy) is following

Date       UT start  JD         Exp.    Filter  OT    Err.  UL(3sigma)
                    (mid, days)  (s)

2022-02-21 19:44:30  2459632.327  40*60   r'    19.20 0.03   22.1
2022-02-21 21:57:59  2459632.416  40*60   r'    19.45 0.02   22.7

The photometry is based on nearby PS1 stars
id         r
J160337.10+311328.5    16.987
J160343.10+311452.9    18.700

The photometry of the the source is brighter than reported either in PS1 
or SDSS DR12, and source  is variable. We can conclude that the 
afterglow is detected and dominate over host galaxy brightness.


GRB_name: GRB220222A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31630
SUBJECT: GRB 220222A: Fermi GBM Final Real-time Localization
DATE:    22/02/22 02:31:50 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 02:21:17 UT on 22 Feb 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220222A (trigger 667189282.835626 / 220222098).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 27.1, Dec = -8.0 (J2000 degrees, equivalent to J2000 01h 48m, -8d 00'), with a statistical uncertainty of 2.3 degrees.

The angle from the Fermi LAT boresight is 59.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220222098/quicklook/glg_skymap_all_bn220222098.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220222098/quicklook/glg_healpix_all_bn220222098.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220222098/quicklook/glg_lc_medres34_bn220222098.gif


GRB_name: GRB220222A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31631
SUBJECT: Fermi GRB 220222A: Global MASTER-Net observations report 
DATE:    22/02/22 04:30:19 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, 
D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, T.Pogrosheva, E.Minkina,
A.Chasovnikov, V.Topolev, V.Grinshpun, D.Kuvshinov,  D. Cheryasov
(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. Gres, N.M. Budnev
(Irkutsk State University, API),

B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez,
M.L.H.Rodriguez (INAOE, OAGH)

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

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


MASTER-OAGH robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) started inspect of the Fermi GRB 220222A ( Fermi GBM team, GCN 31630) errorbox  697 sec after notice time and 725 sec after trigger time at 2022-02-22 02:33:23 UT, with upper limit up to  17.8 mag. The observations began at zenith distance = 65 deg. The sun  altitude  is -18.3 deg. 

The galactic latitude b = -66 deg., longitude l = 162 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1891006

We obtain a following upper limits.  

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

     801 | 2022-02-22 02:33:23 |         MASTER-OAGH | (01h 45m 29.04s , -07d 51m 52.8s) |   C |   150 | 15.9 |        
     801 | 2022-02-22 02:33:23 |         MASTER-OAGH | (01h 44m 58.42s , -07d 24m 02.1s) |   C |   150 | 16.7 |        
    1127 | 2022-02-22 02:38:34 |         MASTER-OAGH | (01h 44m 57.56s , -07d 23m 01.8s) |   C |   180 | 16.5 |        
    1127 | 2022-02-22 02:38:34 |         MASTER-OAGH | (01h 45m 28.44s , -07d 50m 51.4s) |   C |   180 | 15.5 |        
    1469 | 2022-02-22 02:44:16 |         MASTER-OAGH | (01h 45m 36.17s , -07d 51m 45.0s) |   C |   180 | 15.8 |        
    1469 | 2022-02-22 02:44:16 |         MASTER-OAGH | (01h 45m 05.23s , -07d 24m 01.9s) |   C |   180 | 17.0 |        
    1809 | 2022-02-22 02:49:57 |         MASTER-OAGH | (01h 45m 29.37s , -07d 52m 46.6s) |   C |   180 | 16.2 |        
    1809 | 2022-02-22 02:49:57 |         MASTER-OAGH | (01h 44m 58.02s , -07d 25m 04.6s) |   C |   180 | 17.2 |        
    2175 | 2022-02-22 02:57:02 |         MASTER-OAGH | (01h 44m 51.39s , -08d 06m 51.2s) |   C |    60 | 16.8 |        
    2175 | 2022-02-22 02:57:02 |         MASTER-OAGH | (01h 44m 19.36s , -07d 39m 10.7s) |   C |    60 | 17.8 |        
    2396 | 2022-02-22 03:00:43 |         MASTER-OAGH | (01h 44m 23.89s , -06d 14m 09.8s) |   C |    60 | 16.2 |        
    2396 | 2022-02-22 03:00:43 |         MASTER-OAGH | (01h 43m 51.99s , -05d 46m 32.2s) |   C |    60 | 17.4 |        
    2624 | 2022-02-22 03:04:31 |         MASTER-OAGH | (01h 45m 29.85s , -10d 00m 32.3s) |   C |    60 | 16.0 |        
    2624 | 2022-02-22 03:04:31 |         MASTER-OAGH | (01h 44m 56.85s , -09d 32m 54.9s) |   C |    60 | 17.3 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220222A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31633
SUBJECT: GRB 220222A: Swift/BAT-GUANO detection outside the coded FOV
DATE:    22/02/22 14:18:17 GMT
FROM:    Aaron Tohuvavohu at U Toronto  <aaron.tohu@gmail.com>

Aaron Tohuvavohu (U Toronto), Gayathri Raman (PSU), James DeLaunay
(UAlabama), Jamie A. Kennea (PSU), report:

Swift/BAT did not localize GRB 220222A onboard (T0:
2022-02-22T02:21:17 UTC, Fermi/GBM GCN 31630, CALET trigger
#1329531683).

The Fermi and CALET 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,
arXiv:2111.01769), detects the burst with a sqrt(TS) of 17.2 in a
2.048 s analysis time bin.
The observed duration of the burst is ~5 s.

NITRATES results are consistent with a burst coming from outside the
coded FOV, with DeltaLLHOut of -7. The best fit out of FoV location is
consistent with the Fermi/GBM localization (GCN 31630).

See Section 9.1 and Figure 20 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: GRB220219B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31634
SUBJECT: GRB 220219B: Swift ToO observations
DATE:    22/02/22 17:10:13 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a ToO observation of the Konus-Wind GRB 220219B. 
Automated analysis of the XRT data will be presented online at
https://www.swift.ac.uk/ToO_GRBs/00021481

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 Konus-Wind 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: GRB220222B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31636
SUBJECT: GRB 220222B: Fermi GBM Final Real-time Localization
DATE:    22/02/22 19:34:26 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 19:24:07 UT on 22 Feb 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220222B (trigger 667250652.136138 / 220222808).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 191.1, Dec = -33.5 (J2000 degrees, equivalent to J2000 12h 44m, -33d 30'), with a statistical uncertainty of 8.2 degrees.

The angle from the Fermi LAT boresight is 109.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220222808/quicklook/glg_skymap_all_bn220222808.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220222808/quicklook/glg_healpix_all_bn220222808.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220222808/quicklook/glg_lc_medres34_bn220222808.gif


GRB_name: GRB220222B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31637
SUBJECT: Fermi GRB 220222B: Global MASTER-Net observations report 
DATE:    22/02/22 20:15:26 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, 
D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, T.Pogrosheva, E.Minkina,
A.Chasovnikov, V.Topolev, V.Grinshpun, D.Kuvshinov,  D. Cheryasov
(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. Gres, N.M. Budnev
(Irkutsk State University, API),

B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez,
M.L.H.Rodriguez (INAOE, OAGH)

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

A. Gabovich, V.Yurkov 
(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 220222B ( Fermi GBM team, GCN 31636) errorbox  437 sec after notice time and 466 sec after trigger time at 2022-02-22 19:31:53 UT, with upper limit up to  19.1 mag. The observations began at zenith distance = 70 deg. The sun  altitude  is -26.3 deg. 

The galactic latitude b = 29 deg., longitude l = 302 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1891717

We obtain a following upper limits.  

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

     497 | 2022-02-22 19:31:53 |         MASTER-SAAO | (12h 38m 40.72s , -31d 03m 17.8s) |   C |    60 | 18.6 |        
     576 | 2022-02-22 19:33:13 |         MASTER-SAAO | (12h 48m 07.15s , -31d 04m 10.3s) |   C |    60 | 18.5 |        
     656 | 2022-02-22 19:34:33 |         MASTER-SAAO | (12h 36m 35.08s , -32d 58m 40.5s) |   C |    60 | 18.9 |        
     736 | 2022-02-22 19:35:52 |         MASTER-SAAO | (12h 46m 03.63s , -32d 57m 06.5s) |   C |    60 | 18.7 |        
     815 | 2022-02-22 19:37:12 |         MASTER-SAAO | (12h 35m 07.91s , -34d 51m 18.9s) |   C |    60 | 19.0 |        
     895 | 2022-02-22 19:38:32 |         MASTER-SAAO | (12h 44m 45.80s , -34d 52m 03.4s) |   C |    60 | 18.9 |        
     975 | 2022-02-22 19:39:52 |         MASTER-SAAO | (12h 34m 28.35s , -36d 46m 05.6s) |   C |    60 | 19.0 |        
    1055 | 2022-02-22 19:41:12 |         MASTER-SAAO | (12h 44m 20.22s , -36d 47m 01.4s) |   C |    60 | 18.9 |        
    1134 | 2022-02-22 19:42:31 |         MASTER-SAAO | (12h 18m 24.18s , -32d 57m 43.7s) |   C |    60 | 19.1 |        
    1214 | 2022-02-22 19:43:51 |         MASTER-SAAO | (12h 27m 56.03s , -32d 58m 46.3s) |   C |    60 | 19.1 |        
    1475 | 2022-02-22 19:48:12 |         MASTER-SAAO | (12h 38m 39.30s , -31d 03m 19.7s) |   C |    60 | 18.9 |        
    1555 | 2022-02-22 19:49:32 |         MASTER-SAAO | (12h 48m 05.78s , -31d 04m 14.8s) |   C |    60 | 18.7 |        
    1635 | 2022-02-22 19:50:51 |         MASTER-SAAO | (12h 36m 27.81s , -32d 59m 16.5s) |   C |    60 | 18.9 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220219B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31639
SUBJECT: ZTF22aabjpxh/AT2022cva: 1.5m OSN optical observation
DATE:    22/02/22 20:58:41 GMT
FROM:    Youdong HU at IAA-CSIC  <huyoudong072@hotmail.com>

Y.-D. Hu, A. Sota, T.-R. Sun, A. J. Castro-Tirado, M. D. Caballero-Garcia, M. A. Castro Tirado and E. Fernandez-Garcia (IAA-CSIC), on behalf of a larger collaboration, report:

Following the detection of ZTF22aabjpxh/AT2022cva reported by ZTF (Ho et al., GCN 31619) and NICER (Pasham et al. GCNC 31635) which could be consistent with GRB220219B (Svinkin et al. GCNC 31624), images in BVRI bands were obtained at the 1.5m OSN telescope in Granada (Spain) starting on 22 Feb. 2022 at 01:49:51 UT. In single exposures (R-band, 90 s), we measure R = 19.80+-0.13 at 02:22 UT for the above-mentioned optical transient lying at the edge of the nearby galaxy at redshift z = 0.293 as reported by Gemini-North (Fremling et al. GCNC 31629). This detection is consistent with the report from Assy-Turgen (Kim et al. GCNC 31628).

We thank the staff at OSN for their excellent support.


GRB_name: GRB220223A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31640
SUBJECT: GRB 220223A: Fermi GBM Final Real-time Localization
DATE:    22/02/23 02:25:39 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 02:15:16 UT on 23 Feb 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220223A (trigger 667275321.995302 / 220223094).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 26.2, Dec = -20.2 (J2000 degrees, equivalent to J2000 01h 44m, -20d 11'), with a statistical uncertainty of 14.6 degrees.

The angle from the Fermi LAT boresight is 52.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220223094/quicklook/glg_skymap_all_bn220223094.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220223094/quicklook/glg_healpix_all_bn220223094.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220223094/quicklook/glg_lc_medres34_bn220223094.gif


GRB_name: GRB220223A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31642
SUBJECT: Fermi GRB 220223A: Global MASTER-Net observations report 
DATE:    22/02/23 21:30:19 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, 
D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, T.Pogrosheva, E.Minkina,
A.Chasovnikov, V.Topolev, V.Grinshpun, D.Kuvshinov,  D. Cheryasov
(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. Gres, N.M. Budnev
(Irkutsk State University, API),

B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez,
M.L.H.Rodriguez (INAOE, OAGH)

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

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


MASTER-IAC robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Spain (IAC Teide Observatory) started inspect of the Fermi GRB 220223A ( Fermi GBM team, GCN 31640) errorbox  66009 sec after notice time and 66035 sec after trigger time at 2022-02-23 20:35:52 UT, with upper limit up to  18.4 mag. The observations began at zenith distance = 68 deg. The sun  altitude  is -22.1 deg. 

The galactic latitude b = -75 deg., longitude l = 186 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1892013

We obtain a following upper limits.  

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

   66065 | 2022-02-23 20:35:52 |          MASTER-IAC | (01h 50m 28.60s , -08d 28m 32.7s) |   C |    60 | 18.3 |        
   66065 | 2022-02-23 20:35:52 |          MASTER-IAC | (01h 42m 15.18s , -08d 22m 46.6s) |   C |    60 | 17.3 |        
   66145 | 2022-02-23 20:37:12 |          MASTER-IAC | (01h 49m 59.85s , -06d 33m 33.1s) |   C |    60 | 18.2 |        
   66145 | 2022-02-23 20:37:12 |          MASTER-IAC | (01h 41m 48.58s , -06d 27m 45.8s) |   C |    60 | 17.5 |        
   66225 | 2022-02-23 20:38:32 |          MASTER-IAC | (01h 51m 11.47s , -10d 22m 31.5s) |   C |    60 | 18.3 |        
   66225 | 2022-02-23 20:38:32 |          MASTER-IAC | (01h 42m 55.21s , -10d 16m 46.5s) |   C |    60 | 17.2 |        
   66305 | 2022-02-23 20:39:51 |          MASTER-IAC | (01h 49m 37.14s , -04d 41m 32.4s) |   C |    60 | 18.3 |        
   66305 | 2022-02-23 20:39:51 |          MASTER-IAC | (01h 41m 27.20s , -04d 35m 44.1s) |   C |    60 | 17.4 |        
   66385 | 2022-02-23 20:41:11 |          MASTER-IAC | (01h 35m 11.59s , -08d 29m 16.0s) |   C |    60 | 18.2 |        
   66385 | 2022-02-23 20:41:11 |          MASTER-IAC | (01h 26m 57.56s , -08d 23m 31.6s) |   C |    60 | 16.4 |        
   66465 | 2022-02-23 20:42:31 |          MASTER-IAC | (01h 51m 53.10s , -12d 15m 34.1s) |   C |    60 | 18.4 |        
   66465 | 2022-02-23 20:42:31 |          MASTER-IAC | (01h 43m 33.28s , -12d 09m 50.6s) |   C |    60 | 17.1 |        
   66545 | 2022-02-23 20:43:52 |          MASTER-IAC | (01h 35m 41.23s , -10d 23m 31.9s) |   C |    60 | 18.0 |        
   66545 | 2022-02-23 20:43:52 |          MASTER-IAC | (01h 27m 24.16s , -10d 17m 50.7s) |   C |    60 | 15.7 |        
   66625 | 2022-02-23 20:45:11 |          MASTER-IAC | (01h 34m 48.13s , -06d 34m 06.4s) |   C |    60 | 18.0 |        
   66625 | 2022-02-23 20:45:11 |          MASTER-IAC | (01h 26m 36.14s , -06d 28m 21.4s) |   C |    60 | 16.1 |        
   66705 | 2022-02-23 20:46:31 |          MASTER-IAC | (02h 04m 53.12s , -04d 40m 17.5s) |   C |    60 | 18.4 |        
   66705 | 2022-02-23 20:46:31 |          MASTER-IAC | (01h 56m 42.95s , -04d 34m 30.3s) |   C |    60 | 17.5 |        
   66865 | 2022-02-23 20:49:12 |          MASTER-IAC | (01h 34m 29.56s , -04d 40m 44.6s) |   C |    60 | 18.1 |        
   66865 | 2022-02-23 20:49:12 |          MASTER-IAC | (01h 26m 18.95s , -04d 34m 59.5s) |   C |    60 | 16.0 |        
   67146 | 2022-02-23 20:53:52 |          MASTER-IAC | (01h 50m 35.05s , -08d 29m 19.6s) |   C |    60 | 18.2 |        
   67146 | 2022-02-23 20:53:52 |          MASTER-IAC | (01h 42m 20.72s , -08d 23m 31.6s) |   C |    60 | 16.5 |        
   67225 | 2022-02-23 20:55:12 |          MASTER-IAC | (01h 41m 50.05s , -06d 28m 10.6s) |   C |    60 | 17.0 |        
   67225 | 2022-02-23 20:55:12 |          MASTER-IAC | (01h 50m 02.18s , -06d 33m 60.0s) |   C |    60 | 18.0 |        
   67306 | 2022-02-23 20:56:32 |          MASTER-IAC | (01h 51m 08.26s , -10d 23m 01.4s) |   C |    60 | 18.0 |        
   67306 | 2022-02-23 20:56:32 |          MASTER-IAC | (01h 42m 50.99s , -10d 17m 16.6s) |   C |    60 | 16.0 |        
   67386 | 2022-02-23 20:57:52 |          MASTER-IAC | (01h 49m 43.37s , -04d 39m 56.5s) |   C |    60 | 18.1 |        
   67386 | 2022-02-23 20:57:52 |          MASTER-IAC | (01h 41m 32.77s , -04d 34m 06.4s) |   C |    60 | 16.9 |        
   67467 | 2022-02-23 20:59:13 |          MASTER-IAC | (01h 35m 06.20s , -08d 28m 44.1s) |   C |    60 | 17.9 |        
   67547 | 2022-02-23 21:00:33 |          MASTER-IAC | (01h 51m 49.80s , -12d 15m 29.4s) |   C |    60 | 18.1 |        
   67547 | 2022-02-23 21:00:33 |          MASTER-IAC | (01h 43m 28.91s , -12d 09m 48.0s) |   C |    60 | 14.1 |        
   67628 | 2022-02-23 21:01:54 |          MASTER-IAC | (01h 35m 45.04s , -10d 22m 43.3s) |   C |    60 | 17.9 |        
   67708 | 2022-02-23 21:03:14 |          MASTER-IAC | (01h 34m 40.57s , -06d 35m 44.2s) |   C |    60 | 17.8 |        
   67788 | 2022-02-23 21:04:34 |          MASTER-IAC | (01h 56m 47.92s , -04d 35m 00.8s) |   C |    60 | 16.9 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220219B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31643
SUBJECT: ZTF22aabjpxh/AT2022cva (GRB 220219B): Mondy optical observations
DATE:    22/02/23 22:36:04 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed ZTF22aabjpxh/AT2022cva discovered by ZTF (Ho et al., GCN 
31619) with AZT-33IK telescope of Mondy observatory on 2022-02-21  and 
2022-02-22. ZTF22aabjpxh/AT2022cva was observed also in optic (Kim  et 
al., GCN 31628; Hu et al., GCN 31639) and in X-ray by NICER (Pasham et 
al., GCN 31635). ZTF22aabjpxh/AT2022cva is considered the likely 
afterglow of GRB 220219B (Ho et al., GCN 31619; Svinkin et al., GCN 31624).

We clearly detect the SDSS galaxy at z=0.293 (Fremling et al., GCN 
31629). Due to non-optimal seeing we could not  discriminate the 
afterglow from the galaxy. We use aperture  photometry and preliminary 
photometry of a source (afterglow+host  galaxy) is following

Date       UT start  JD         Exp.    Filter  OT    Err.  UL(3sigma)
                     (mid, days)  (s)

2022-02-21 19:30:32  2.43966  30*120   R    19.19    0.03    22.8
2022-02-22 19:31:06  3.43936  29*120   R    19.34    0.03    22.8

The photometry is based on nearby SDSS DR12 stars
id                  r      R(Lupton) V(Lupton)
J160337.10+311328.5 16.987 16.79     17.19
J160343.10+311452.9 18.700 18.51     18.90

Assuming the host galaxy has R = 19.7 we subtract a host galaxy flux 
from a flux of the source (afterglow+host  galaxy) and estimated power 
law index of a light curve of the afterglow as -1.2,  which is typical 
for a GRB afterglow.


GRB_name: GRB220219B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31644
SUBJECT: GRB 220219B: Swift-XRT observations
DATE:    22/02/24 11:18:42 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

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

Swift-XRT has performed follow-up observations of GRB 220219B (Svinkin
et al., GCN Circ. 31624), collecting 3.5 ks of Photon Counting (PC)
mode data between T0+322.5 ks and T0+369.3 ks. 

One uncatalogued X-ray source has been detected at a position
consistent with the GRB optical afterglow candidate
ZTF22aabjpxh/AT2022cva (Ho et al., GCN Circ. 31619). The X-ray source 
is below the RASS limit and shows no definitive signs of fading.
Details of this source are given below:

Source 1:
  RA (J2000):  240.91414  =  16:03:39.39
  Dec (J2000): +31.23404  =  +31:14:02.5
  Error: 2.8 arcsec (radius, 90% conf. [Enhanced position])
  Count-rate: 0.0250 [+0.0032, -0.0031] ct s^-1   
  Flux: (1.06 [+0.14, -0.13])e-12 erg cm^-2 s^-1 (observed, 0.3-10 keV)


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/00021481.

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


GRB_name: GRB220222A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31645
SUBJECT: GCN Circ.draft on GRB 220222A
DATE:    22/02/24 16:15:25 GMT
FROM:    Anna Ridnaia at Ioffe Institute  <ridnaia@mail.ioffe.ru>

Dear colleagues,

Find below a draft of our GCN on GRB 220222A.

Best regards,
Anna

IPN triangulation of GRB 220222A

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

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

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM 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 220222A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 31630;
Swift/BAT-GUANO detection: Tohuvavohu et al., GCN Circ. 31633)
has been detected by Fermi (GBM trigger 667189282), Konus-Wind,
Swift (BAT), and Mars-Odyssey (HEND), so far,
at about 8477 s UT (02:21:17).
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:
   32.630 (02h 10m 31s) -14.008 (-14d 00' 31")
 Corners:
   38.241 (02h 32m 58s) -24.843 (-24d 50' 33")
   38.323 (02h 33m 18s) -25.232 (-25d 13' 56")
   24.966 (01h 39m 52s)  +3.526 ( +3d 31' 33")
   24.595 (01h 38m 23s)  +4.715 ( +4d 42' 55")
 ---------------------------------------------
The error box area is 3.6 sq. deg, and its maximum
dimension is 32.8 deg (the minimum one is 6.7 arcmin).
The Sun distance was 51 deg.

This box may be improved.

The IPN localization is consistent with, but reduces the area of, the
Fermi GBM Final Real-time localization (GCN Circ. 31630).

A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB220222_T08477/IPN/

The time history and spectrum will be given in forthcoming
GCN Circulars.


GRB_name: GRB220219B
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31646
SUBJECT: Konus-Wind observation of GRB 220219B
DATE:    22/02/25 05:54:26 GMT
FROM:    Anastasia Tsvetkova at Ioffe Institute  <tsvetkova@mail.ioffe.ru>

A. Tsvetkova, D. Frederiks, A. Lysenko, A. Ridnaia, D. Svinkin,
M. Ulanov, and T. Cline on behalf of the Konus-Wind team, report:

The long-duration GRB 220219B
(IPN triangulation: Svinkin et al., GCN 31624),
consistent with the optical transient ZTF22aabjpxh/AT2022cva
reported by ZTF (Ho et al., GCN 31619),
triggered Konus-Wind at T0=34045.350 s UT (09:27:25.350).

The burst light curve consists of two broad pulses:
the first one lasts from ~T0-34 s to ~T0+13 s peaking at ~T0,
the second pulse lasts from ~T0+18 s to ~T0+45 s peaking at ~T0+20 s,
The emission is seen up to ~1 MeV.

As observed by Konus-Wind, the burst had
a fluence of the first pulse 1.21(-0.15,+0.16)x10^-5 erg/cm^2,
a fluence of the whole burst 1.76(-0.14,+0.12)x10^-5 erg/cm^2,
and a 64-ms peak energy flux, measured from T0-0.064 s,
of 1.76(-0.27,+0.52)x10^-6 erg/cm^2/s
(all in the 20 keV - 10 MeV energy range).

Since the main fraction of the first pulse was detected
before the trigger, its spectral analysis was performed using
the KW 3-channel light curve data.

Modelling its spectrum (measured from T0-33.723 s to T0+13.380 s)
by the exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep),
yields alpha = -1.86(-0.09,+4.36) and Ep = 39(-24,+27) keV.

Fitting the most intense part of the first pulse
(measured from T0-1.340 s to T0+1.604 s)
with by the exponential cutoff model yields
alpha = -1.75(-0.20,+4.25) and Ep = 61(-46,+24) keV.

The spectrum of the second emission pulse
(from T0+16.640 s to T0+49.408 s)
is well described by a simple power law (PL) with the photon PL index
of 2.60(-0.10,+0.10) and chi2/dof = 69.5/61.

Assuming the redshift z = 0.293 (Fremling et al., GCN 31629)
and a standard cosmology with H_0 = 67.3 km/s/Mpc, Omega_M = 0.315,
and Omega_Lambda = 0.685 (Planck Collaboration, 2014),
we estimate the following burst rest-frame parameters:
the isotropic energy release in the first pulse is
Eiso = 2.75(-0.34,+0.36)x10^51 erg,
the isotropic peak luminosity is Liso = 5.17(-0.79,+1.53)x10^50 erg/s;
the rest-frame peak energy of the first pulse is Epiz = 50(-31,+35) keV;
and the rest-frame peak energy of the 'peak' spectrum is
Eppz = 79(-59,+31) keV.

With these values, GRB 220219B is within 68% prediction bands for
for both 'Amati' and 'Yonetoku' relations for the sample of >300 long KW
GRBs with known redshifts (Tsvetkova et al., 2021, ApJ, 908, 83),
see http://www.ioffe.ru/LEA/GRBs/GRB220219_T34045/GRB220219B_rest_frame.pdf

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB220219_T34045/

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB220101A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31648
SUBJECT: GRB 220101A: The first example of a Petanova
DATE:    22/02/25 11:38:50 GMT
FROM:    Remo Rufinni at ICRA  <ruffini@icra.it>

R. Ruffini, Y. Aimuratov, L. Becerra, C.L. Bianco, Y-C. Chen, C. Cherubini,
Y.F. Cai, S. Eslamzadeh, S. Filippi, M. Karlica, Liang Li, G.J. Mathews, R.
Moradi, M. Muccino, G.B, Pisani, F. Rastegar Nia, J.A. Rueda, N. Sahakyan,
Y. Wang,  S.S. Xue,  Y.F. Yuan, Y.L. Zheng, on behalf of ICRA, ICRANet and
USTC team, report:

We confirm the results of our previous GCN (Ruffini et al. 2022, GCN
31465). Following the release of the X-ray afterglow (Tohuvavohu et al.
2022, GCN 31347) and the GeV data (Arimoto et al. 2022, GCN 31350) of this
source, we can estimate the total (keV+MeV+GeV) isotropic energy (see e.g.
Ruffini et al. 2021, MNRAS 504, 5301) to be ~6E54 erg, making this GRB the
most powerful GRB in 26 years (a "Petanova"). The period of the new neutron
star (see e.g. Ruffini et al. 2021, MNRAS 504, 5301) generating the X-ray
afterglow is ~1 ms, the initial mass of the BH (see e.g. Ruffini et al.
2019 ApJ 886, 82) is 6.15 solar mass, the spin parameter is 0.95, and the
irreducible mass is 4.98 solar masses (see Fig. 1). The peak of the
bolometric flux of supernova is of the order of 1E-17 erg/s/cm^2 and will
appear in 73+/-15 days after the GRB trigger, with emissions lasting ~ one
month peaking in different infrared bands. The observational follow up
of this source is encouraged.

Fig. 1: http://www.icranet.org/docs/GRB220101A.pdf


GRB_name: GRB220222A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31649
SUBJECT: IPN triangulation of GRB 220222A
DATE:    22/02/25 12:51:38 GMT
FROM:    Anna Ridnaia at Ioffe Institute  <ridnaia@mail.ioffe.ru>

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

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

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM 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 220222A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 31630;
Swift/BAT-GUANO detection: Tohuvavohu et al., GCN Circ. 31633)
has been detected by Fermi (GBM trigger 667189282), Konus-Wind,
Swift (BAT), and Mars-Odyssey (HEND), so far,
at about 8477 s UT (02:21:17).
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:
   32.630 (02h 10m 31s) -14.008 (-14d 00' 31")
 Corners:
   38.241 (02h 32m 58s) -24.843 (-24d 50' 33")
   38.323 (02h 33m 18s) -25.232 (-25d 13' 56")
   24.966 (01h 39m 52s)  +3.526 ( +3d 31' 33")
   24.595 (01h 38m 23s)  +4.715 ( +4d 42' 55")
 ---------------------------------------------
The error box area is 3.6 sq. deg, and its maximum
dimension is 32.8 deg (the minimum one is 6.7 arcmin).
The Sun distance was 51 deg.

This box may be improved.

The IPN localization is consistent with, but reduces the area of, the
Fermi GBM Final Real-time localization (GCN Circ. 31630).

A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB220222_T08477/IPN/

The time history and spectrum will be given in forthcoming
GCN Circulars.

This GCN is the corrected version of GCN 31645.
We apologize for any confusion this may have caused.


GRB_name: GRB220222A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31657
SUBJECT: Konus-Wind detection of GRB 220222A
DATE:    22/02/28 18:52:36 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin,
A. Tsvetkova,  M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:

The long-duration GRB 220222A
(Fermi-GBM detection: The Fermi GBM team, GCN 31630;
Swift/BAT-GUANO detection: Tohuvavohu et al., GCN 31633;
IPN localization: Kozyrev et al., GCN 31649)
triggered Konus-Wind (KW) at T0=8476.873 s UT (02:21:16.873).

The burst light curve shows a FRED-like pulse which starts at ~T0-0.5 s,
peaks at ~T0, and has the total duration of ~5.0 s.
Also, a short pulse is seen the KW light curve at ~T0+7.1 s.
The emission is seen up to ~1 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB220222_T08477/

As observed by Konus-Wind, the burst had
a fluence of (3.6 Â± 0.6)x10^-6 erg/cm^2 and
a 64-ms peak energy flux, measured from T0-0.064,
of (2.0 Â± 0.3)x10^-6 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst (measured from T0 to T0+8.448 s)
is adequately 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 = -0.60(-0.47,+0.60) and Ep = 187(-35,+63) keV (chi2 = 92/60 dof).
Fitting this spectrum by a Band function yields the same alpha and Ep,
and an upper limit on the high energy photon index beta of -2.3 (chi2 = 93/59 dof).

All the quoted errors are estimated at the 90% confidence level.
All the presented results are preliminary.


GRB_name: GRB220228A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31658
SUBJECT: GRB 220228A: Fermi GBM Final Localization
DATE:    22/02/28 21:52:12 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

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

At 10:30:05.92 UT on 28 Feb 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220228A (trigger 667737010 / 220228438).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 321.0, Dec = -16.9 (J2000 degrees, equivalent to J2000 21h 24m, -16d 54'), with a statistical uncertainty of 8.5 degrees.

The angle from the Fermi LAT boresight is 28.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220228438/quicklook/glg_skymap_all_bn220228438.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220228438/quicklook/glg_healpix_all_bn220228438.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220228438/quicklook/glg_lc_medres34_bn220228438.gif


GRB_name: GRB220228A
Detection_method: Fermi LAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31659
SUBJECT: GRB 220228A: Fermi-LAT detection
DATE:    22/02/28 22:06:43 GMT
FROM:    Niccolo Di Lalla at Stanford U  <niccolo.dilalla@stanford.edu>

N. Omodei, N. Di Lalla (Stanford University), R. Pillera (INFN Bari) 
report on behalf of the Fermi-LAT team:

On February 28, 2022, Fermi-LAT detected high-energy emission from GRB 
220228A, which was also detected by**Fermi-GBM (trigger 667737010 / 
220228438, GCN 31658).

The best LAT on-ground location is found to be

RA, Dec = 311.2, -22.7 (degrees, J2000)

with an error radius of 0.7 deg (90 % containment, statistical error 
only). This was 23 deg from the LAT boresight at the time of the trigger:

T0 = 10:30:05.92 UT.

The data from the Fermi-LAT show a significant increase in the event 
rate that is spatially and temporally correlated with the GBM emission 
with high significance. The photon flux above 90 MeV in the time 
interval 0-1000s after the GBM trigger is 4E-6 Â± 1E-6 ph/cm2/s.

The estimated photon index above 90 MeV is -2.9 Â± 0.4.

The highest-energy photon is a 323 MeV**event which is observed 77 
seconds after the GBM trigger.

A Swift ToO has been requested for this burst.

The Fermi-LAT point of contact for this burst is Roberta 
Pillera**(roberta.pillera@ba.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: GRB220228A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31660
SUBJECT: GRB 220228A: Fermi GBM observation
DATE:    22/02/28 22:26:02 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

J. Wood (NASA/MSFC) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 10:30:05.92 UT on 28 Feb 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 220228A (trigger 667737010 / 220228438)
which was also detected by the Fermi LAT (N. Omodei et al. 2022, GCN 31659).
The GBM on-ground location (GCN 31658) is consistent with the LAT position.

The GBM light curve consists of a single pulse
with a duration (T90) of about 12.5 s (50-300 keV).
The time-averaged spectrum from T0-7 s to T0+6 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is 1.7 +/- 0.2 and
the cutoff energy, parameterized as Epeak, is 106 +/- 46 keV

The event fluence (10-1000 keV) in this time interval is
((1.1 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-0.5 s in the 10-1000 keV band
is 3.1 +/- 0.2 ph/s/cm^2.

A power law function fits the spectrum equally well
with index -1.9 +/- 0.1.

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: GRB220302A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31661
SUBJECT: GRB 220302A: Swift detection of a burst
DATE:    22/03/02 07:57:49 GMT
FROM:    Kim Page at U.of Leicester  <kimlpage1978@gmail.com>

E. Troja (NASA/GSFC/UMCP), C. Gronwall (PSU),
K. L. Page (U Leicester), D. M. Palmer (LANL) and
T. M. Parsotan (GSFC/UMBC/CRESSTII) report on behalf of the Neil
Gehrels Swift Observatory Team:

At 07:40:19 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 220302A (trigger=1094950).  Swift did not slew to the burst. 
The BAT on-board calculated location is 
RA, Dec 301.432, +49.389 which is 
   RA(J2000) = 20h 05m 44s
   Dec(J2000) = +49d 23' 20"
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 20 sec.  The peak count rate
was ~1156 counts/sec (15-350 keV), at ~2 sec after the trigger. 

Swift is currently restarting after a reaction wheel failure, so
automatic slews to GRBs are turned off.  Therefore there will be
no XRT or UVOT observations at this time. 

Burst Advocate for this burst is E. Troja (nora.gsfc 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: GRB220302A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31662
SUBJECT: Swift GRB 220302A: Global MASTER-Net observations report 
DATE:    22/03/02 08:36:31 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, 
D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, T.Pogrosheva, E.Minkina,
A.Chasovnikov, V.Topolev, V.Grinshpun, D.Kuvshinov,  D. Cheryasov
(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. Gres, N.M. Budnev
(Irkutsk State University, API),

B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez,
M.L.H.Rodriguez (INAOE, OAGH)

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

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


MASTER-OAGH robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) was pointed to the Swift GRB 220302A ( E. Troja et al., GCN 31661) errorbox  2514 sec after notice time and 2575 sec after trigger time at 2022-03-02 08:23:15 UT, with upper limit up to  16.6 mag. The observations began at zenith distance = 87 deg. The sun  altitude  is -63.3 deg. 

The galactic latitude b =  9 deg., longitude l = 84 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1899637

We obtain a following upper limits.  

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

    2606 |         MASTER-OAGH |   C |    60 | 15.8 |        
    2687 |         MASTER-OAGH |   C |    60 | 15.0 |        
    2769 |         MASTER-OAGH |   C |    60 | 15.7 |        
    3051 |         MASTER-OAGH |   C |    60 | 16.6 |        
    3133 |         MASTER-OAGH |   C |    60 | 15.8 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220222A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31663
SUBJECT: GRB 220222A: CALET Gamma-Ray Burst Monitor detection
DATE:    22/03/02 09:09:24 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

S. Ricciarini (U of Florence),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
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), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:

The GRB 220222A (Fermi GBM Final Real-time Localization: Fermi GBM team,
GCN Circ. 31630; Swift/BAT-GUANO detection: Tohuvavohu et al., GCN
Circ. 31633; IPN triangulation: Kozyrev et al., GCN Circ. 31649;
Konus-Wind detection: Frederiks et al., GCN Circ. 31657;
https://gcn.gsfc.nasa.gov/other/220222A.gcn3) triggered the CALET Gamma-ray
Burst Monitor (CGBM) at 02:21:16.664 UTC on 22 February 2022
(http://cgbm.calet.jp/cgbm_trigger/flight/1329531683/index.html).
The burst signal was seen only by the SGM detector.

The burst light curve shows a single weak pulse which starts at T+1.3 sec,
peaks at T+2.4 sec,and ends at T+3.0 sec. The T90 and T50 durations
measured by the SGM data are 1.5 +- 0.4 sec and 0.6 +- 0.5 sec
(40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1329531683/

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


GRB_name: GRB220302A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31664
SUBJECT: GRB 220302A: Swift afterglow detection
DATE:    22/03/02 17:03:47 GMT
FROM:    Kim Page at U.of Leicester  <kimlpage1978@gmail.com>

E. Troja (NASA/GSFC/UMCP), C. Gronwall (PSU), J. A. Kennea (PSU),
K. L. Page (U Leicester), D. M. Palmer (LANL),
T. M. Parsotan (GSFC/UMBC/CRESSTII) and A. Tohuvavohu (U Toronto)
report on behalf of the Neil Gehrels Swift Observatory Team:

Continuing the recovery from the Reaction Wheel anomaly, Swift has performed a
follow-up observation of GRB 220302A which occurred at 07:40:19 UT (Troja et al., 
GCN 31661). 

The XRT began observing the field at 16:41:18.7 UT, 32459.3 seconds
after the BAT trigger. Using promptly downlinked data we find an
uncatalogued X-ray source located at RA, Dec 301.43151, 49.38868 which
is equivalent to:
   RA(J2000)  = 20h 05m 43.56s
   Dec(J2000) = +49d 23' 19.2"
with an uncertainty of 4.7 arcseconds (radius, 90% containment). This
location is 1.6 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. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 3.44
x 10^21 cm^-2 (Willingale et al. 2013). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 32463 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
100% of the XRT 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 XRT 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 0.216. 

Burst Advocate for this burst is E. Troja (nora.gsfc 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: GRB220302A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31666
SUBJECT: GRB 220302A: Enhanced Swift-XRT position
DATE:    22/03/02 23:50:27 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 1271 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 220302A, 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 = 301.43044, +49.38699 which is equivalent
to:

RA (J2000): 20h 05m 43.30s
Dec (J2000): +49d 23' 13.1"

with an uncertainty of 2.9 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: GRB220302A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31669
SUBJECT: GRB 220302A: BOOTES-5/JGT optical upper limit
DATE:    22/03/03 17:13:47 GMT
FROM:    Youdong HU at IAA-CSIC  <huyoudong072@hotmail.com>

Y.-D. Hu, E. Fernandez-Garcia, T.-R. Sun, A. J. Castro-Tirado, M.D. Caballero-Garcia and R. Sanchez-Ramirez (IAA-CSIC), D. Hiriart and W. H. Lee (UNAM), C. J. Perez del Pulgar and I. Carrasco (UMA), I. H. Park (SKKU) on behalf of a larger collaboration, report:

Following the detection of GRB 220302A by Swift (Troja et al. GCNC 31661), the BOOTES-5/JGT 0.6m robotic telescope at Observatorio Astronomico Nacional in San Pedro Martir (Mexico) automatically started to observe the GRB localization starting on Mar 2 at 12:59 UT (~5.3 hours after trigger). In the co-added image (5 x 60 s exposures in the clear filter), no optical afterglow is detected within the Swift/XRT error region (Troja et al. GCNC 31664, Osborne et al. GCNC 31666) down to 20.3 mag. This non-detection is consistent with the UVOT (Troja et al. GCNC 31664) and MASTER observation (Lipunov et al. GCNC 31662).

We thank the staff at Observatorio Astronomico Nacional in San Pedro Martir for their excellent support.


GRB_name: GRB220304A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31672
SUBJECT: GRB 220304A: Fermi GBM Final Real-time Localization
DATE:    22/03/04 05:39:15 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 05:28:58 UT on 4 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220304A (trigger 668064543.786552 / 220304228).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 245.0, Dec = -35.7 (J2000 degrees, equivalent to J2000 16h 19m, -35d 42'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 145.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220304228/quicklook/glg_skymap_all_bn220304228.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220304228/quicklook/glg_healpix_all_bn220304228.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220304228/quicklook/glg_lc_medres34_bn220304228.gif


GRB_name: GRB220302A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31673
SUBJECT: GRB 220302A: Swift-XRT refined Analysis
DATE:    22/03/04 06:42:37 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

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

We have analysed 3.4 ks of XRT data for GRB 220302A (Troja et al. GCN
Circ. 31661), from 32.5 ks to 160.8 ks after the  BAT trigger. The data
are entirely in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Osborne et al. (GCN Circ. 31666).

The light curve can be modelled with a power-law decay with a decay
index of alpha=0.7 (+0.5, -0.4).

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01094950.

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


GRB_name: GRB220304A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31674
SUBJECT: GRB 220304A: BALROG localization (Fermi Trigger  / GRB 220304228)
DATE:    22/03/04 07:33:33 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

B. Biltzinger, F. Kunzweiler, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
 at 05:28:58 on 04 March 2022 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) = 249.0+/-0.6 deg
Decl.(2000.0) = -37.9+/-0.3 deg
We estimate an additional systematic error of 1 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB220304228/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB220304228/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB220304228/json

                        


GRB_name: GRB220304A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31676
SUBJECT: Fermi GRB 220304A: Global MASTER-Net observations report 
DATE:    22/03/04 08:30:14 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, 
D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, T.Pogrosheva, E.Minkina,
A.Chasovnikov, V.Topolev, V.Grinshpun, D.Kuvshinov,  D. Cheryasov
(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. Gres, N.M. Budnev
(Irkutsk State University, API),

B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez,
M.L.H.Rodriguez (INAOE, OAGH)

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

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


MASTER-IAC robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Spain (IAC Teide Observatory) started inspect of the Fermi GRB 220304A ( Fermi GBM team, GCN 31672) errorbox  141 sec after notice time and 148 sec after trigger time at 2022-03-04 05:31:27 UT, with upper limit up to  17.7 mag. The observations began at zenith distance = 65 deg. The sun  altitude  is -25.8 deg. 

The galactic latitude b = 10 deg., longitude l = 344 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1901611

We obtain a following upper limits.  

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

     164 | 2022-03-04 05:31:27 |          MASTER-IAC | (16h 31m 09.59s , -34d 58m 25.0s) |  P| |    30 | 16.7 |        
     164 | 2022-03-04 05:31:27 |          MASTER-IAC | (16h 32m 18.05s , -35d 06m 08.0s) |  P- |    30 | 16.1 |        
     287 | 2022-03-04 05:33:20 |          MASTER-IAC | (16h 31m 06.66s , -34d 57m 41.0s) |  P| |    50 | 17.0 |        
     287 | 2022-03-04 05:33:20 |          MASTER-IAC | (16h 32m 15.15s , -35d 05m 23.2s) |  P- |    50 | 16.7 |        
     367 | 2022-03-04 05:34:30 |          MASTER-IAC | (16h 31m 07.06s , -34d 56m 42.3s) |  P| |    70 | 17.1 |        
     367 | 2022-03-04 05:34:30 |          MASTER-IAC | (16h 32m 15.46s , -35d 04m 24.5s) |  P- |    70 | 16.9 |        
     462 | 2022-03-04 05:36:00 |          MASTER-IAC | (16h 31m 12.49s , -34d 57m 44.8s) |  P| |    80 | 17.2 |        
     462 | 2022-03-04 05:36:00 |          MASTER-IAC | (16h 32m 20.78s , -35d 05m 26.9s) |  P- |    80 | 16.9 |        
     571 | 2022-03-04 05:37:40 |          MASTER-IAC | (16h 31m 06.38s , -34d 58m 46.1s) |  P| |   100 | 17.3 |        
     571 | 2022-03-04 05:37:40 |          MASTER-IAC | (16h 32m 14.60s , -35d 06m 28.1s) |  P- |   100 | 17.0 |        
     706 | 2022-03-04 05:39:40 |          MASTER-IAC | (16h 17m 26.64s , -35d 37m 37.7s) |  P| |   130 | 17.6 |        
     706 | 2022-03-04 05:39:40 |          MASTER-IAC | (16h 18m 35.17s , -35d 45m 20.1s) |  P- |   130 | 17.4 |        
     872 | 2022-03-04 05:42:10 |          MASTER-IAC | (16h 17m 23.11s , -35d 36m 33.5s) |  P| |   160 | 17.6 |        
     872 | 2022-03-04 05:42:10 |          MASTER-IAC | (16h 18m 31.47s , -35d 44m 16.5s) |  P- |   160 | 17.5 |        
    2103 | 2022-03-04 06:03:31 |          MASTER-IAC | (16h 15m 06.77s , -34d 47m 40.2s) |   C |    60 | 17.5 |        
    2103 | 2022-03-04 06:03:31 |          MASTER-IAC | (16h 25m 04.10s , -34d 54m 02.7s) |   C |    60 | 17.3 |        
    2183 | 2022-03-04 06:04:51 |          MASTER-IAC | (16h 30m 06.12s , -36d 49m 14.5s) |   C |    60 | 17.3 |        
    2183 | 2022-03-04 06:04:51 |          MASTER-IAC | (16h 19m 54.38s , -36d 42m 50.0s) |   C |    60 | 17.7 |        
    2263 | 2022-03-04 06:06:11 |          MASTER-IAC | (16h 21m 25.45s , -33d 02m 05.6s) |   C |    60 | 17.4 |        
    2422 | 2022-03-04 06:08:51 |          MASTER-IAC | (16h 06m 35.72s , -34d 53m 49.9s) |   C |    60 | 17.2 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220304A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31677
SUBJECT: GRB 220304A: Swift/BAT-GUANO detection outside the coded FOV
DATE:    22/03/04 16:15:57 GMT
FROM:    Aaron Tohuvavohu at U Toronto  <aaron.tohu@gmail.com>

James DeLaunay (UAlabama), Aaron Tohuvavohu (U Toronto), Gayathri
Raman (PSU), Jamie A. Kennea (PSU), report:

Swift/BAT did not localize GRB 220304A onboard (T0: 2022-03-04T05:28:58
 UTC, Fermi/GBM GCN 31672).

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,
arXiv:2111.01769), detects the burst with a sqrt(TS) of 49 in a 16.384
s analysis time bin, the longest time bin of the search.
The duration of the burst is at least 30 seconds.

NITRATES results indicate a burst coming from outside the coded FOV,
with DeltaLLHOut of -55. The best fit location is consistent with the
Fermi/GBM RoboBA (GCN 31672), and BALROG (GCN 31674) localizations.

See Section 9.1 and Figure 20 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: GRB220302A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31682
SUBJECT: GRB 220302A: Swift/UVOT Upper Limits 
DATE:    22/03/05 03:37:18 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <mhs18@psu.edu>

M. H. Siegel (PSU) and E. Troja (NASA/GSFC/UMCP)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 220302A
32464 s after the BAT trigger (Troja et al., GCN Circ. 31661).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 31666) 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         32464        32614          147         >19.9
white            32464        32614          147         >19.9
v                32621        33528          885         >19.2
m2               33533        34194          651         >19.7

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.217 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB220219B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31683
SUBJECT: ZTF22aabjpxh/AT2022cva (GRB 220219B): continued optical observations, SN signature search
DATE:    22/03/05 10:45:37 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We are continuing observations of ZTF22aabjpxh/AT2022cva discovered by 
ZTF (Ho et al., GCN 31619) with AZT-33IK telescope of Mondy observatory 
and Zeiss-1000 on 2022-02-21 between 2022-02-23 and 2022-03-04, i.e. upt 
13.4 days after GRB 220219B trigger. ZTF22aabjpxh/AT2022cva was observed 
in optic (Kim  et al., GCN 31628; Hu et al., GCN 31639) and in X-ray by 
NICER (Pasham et al., GCN 31635) and XRT/Swift (Beardmore et al., GCN 
31644). ZTF22aabjpxh/AT2022cva is considered the likely afterglow of GRB 
220219B (Ho et al., GCN 31619; Svinkin et al., GCN 31624; Tsvetkova et 
al., GCN 31646).

We clearly detect  the SDSS galaxy at z=0.293 (Fremling et al., GCN 
31629). Due to non-optimal seeing we could not  discriminate the 
afterglow from the galaxy. We use aperture  photometry of a source 
(afterglow + host  galaxy). Based on our  preliminary photometry we plot 
  a light curve  of the source, see upper panel of the Figure in

http://grb.rssi.ru/GRB220219B/GRB220219B_AT2022cva_LC.png

To estimate power law index of the afterglow we fit our photometric data 
by a single power law + constant host galaxy flux. The host galaxy fit 
is R = 19.68+/-0.05 and PL index alpha = -1.75+/-0.4. The light curve of 
the afterglow after subtraction of a flux of the host is presented at 
bottom panel of the Figure in

http://grb.rssi.ru/GRB220219B/GRB220219B_AT2022cva_LC.png

Power Law index is broadly compatible with the index of -1.6 obtained in 
XRT observations up to ~8 days, see XRT light curve at

https://www.swift.ac.uk/xrt_live_cat/00021481/

We may conclude the source ZTF22aabjpxh/AT2022cva is the optical 
afterglow of GRB 220219B.

Since the redshift of GRB 220219B (ZTF22aabjpxh/AT2022cva) is z=0.293 
(Fremling et al., GCN 31629) we are searching for a supernova signature. 
  Based on the Figure referenced above we still don't see any conclusive 
evidence for the existence of SN.

We urge further multicolour observations to confirm/search for SN 
associated with GRB 220219B.


GRB_name: GRB220305A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31684
SUBJECT: GRB 220305A: Swift detection of a burst
DATE:    22/03/05 16:21:41 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

R. Caputo (GSFC), C. Gronwall (PSU), J.D. Gropp (PSU),
J. A. Kennea (PSU), A. Y. Lien (U Tampa), K. L. Page (U Leicester),
D. M. Palmer (LANL) and T. M. Parsotan (GSFC/UMBC/CRESSTII) report on
behalf of the Neil Gehrels Swift Observatory Team:

At 16:13:08 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 220305A (trigger=1095215).  Due to a viewing constraint,
Swift did not immediately slew.  The BAT on-board calculated location is 
RA, Dec 107.584, -37.708 which is 
   RA(J2000) = 07h 10m 20s
   Dec(J2000) = -37d 42' 29"
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 40 sec.  The peak count rate
was ~1500 counts/sec (15-350 keV), at ~0 sec after the trigger. 

Due to an observing constraint, Swift will not slew until T0+46.5
minutes. There will be no XRT or UVOT data until this time. 

Burst Advocate for this burst is R. Caputo (regina.caputo AT nasa.gov). 
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: GRB220305A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31685
SUBJECT: GRB 220305A: Swift-XRT observations
DATE:    22/03/05 17:44:49 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

D.N. Burrows (PSU), J.A. Kennea (PSU), S. Campana (INAF-OAB), G.
Cusumano (INAF-IASF PA), P.A. Evans (U. Leicester) and J.P. Osborne (U.
Leicester) report on behalf of the Swift-XRT team:

The XRT began observing the field of GRB 220305A at 17:03:25.5 UT,
3016.9 seconds after the BAT trigger. Using promptly downlinked data we
find a fading, uncatalogued X-ray source located at RA, Dec 107.59841,
-37.68016 which is equivalent to:
   RA(J2000)  = 07h 10m 23.62s
   Dec(J2000) = -37d 40' 48.6"
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This
location is 108 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. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (2.59 x
10^21 cm^-2, Willingale et al. 2013), with an excess column of 8.1
(+6.60/-5.31) x 10^21 cm^-2 (90% confidence). 


GRB_name: GRB220305A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31686
SUBJECT: Swift GRB 220305A: Global MASTER-Net observations report 
DATE:    22/03/05 17:56:47 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, 
D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, T.Pogrosheva, E.Minkina,
A.Chasovnikov, V.Topolev, V.Grinshpun, D.Kuvshinov,  D. Cheryasov
(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. Gres, N.M. Budnev
(Irkutsk State University, API),

B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez,
M.L.H.Rodriguez (INAOE, OAGH)

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

A. Gabovich, V.Yurkov 
(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) was pointed to the Swift GRB 220305A ( R. Caputo et al., GCN 31684) errorbox  5464 sec after notice time and 5486 sec after trigger time at 2022-03-05 17:44:35 UT, with upper limit up to  16.4 mag. Observations started at twilight.  The observations began at zenith distance = 16 deg. The sun  altitude  is -8.2 deg. 

The galactic latitude b = -12 deg., longitude l = 249 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1902942

We obtain a following upper limits.  

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

    5577 |         MASTER-SAAO | P\  |   180 | 16.0 |        
    5776 |         MASTER-SAAO | P\  |   180 | 16.4 |        


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


GRB_name: GRB220305A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31688
SUBJECT: GRB 220305A: Enhanced Swift-XRT position
DATE:    22/03/05 20:29:02 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 1712 s of XRT Photon Counting mode data and 5 UVOT
images for GRB 220305A, 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 = 107.59853, -37.68033 which is equivalent
to:

RA (J2000): 07h 10m 23.65s
Dec (J2000): -37d 40' 49.2"

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: GRB220305A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31689
SUBJECT: GRB 220305A: Fermi GBM observation
DATE:    22/03/05 23:40:22 GMT
FROM:    Joe Mangan at UCD  <joseph.mangan@ucdconnect.ie>

R. Dunwoody (UCD), J. Mangan (UCD) and C.Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 11:33:20.48 UT on 05 March 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 220305A (trigger 668172805 / 220305481).

The on-ground calculated location, using the GBM trigger
data, is RA = 174, DEC = -34 (J2000 degrees,
equivalent to 11 h 36 m, -34 d 00 '), with a statistical uncertainty
of 1.5 degrees.

The angle from the Fermi LAT boresight at the GBM trigger time is 35 degrees.

The GBM light curve consists of three emission episodes, the most
prominent occurring around T0+50s, with a duration (T90) of about
172.8 s (50-300 keV).

The time-averaged spectrum for the first emission episode, from
T0-12.3 to T0+12.3, is best fit by a power law function with an
exponential high-energy cutoff. The power law index is -0.6 +/- 0.5
and the cutoff energy, parameterized as Epeak, is 60.9 +/- 9.1 keV.
The event fluence (10-1000 keV) in this time interval is (6.8 +/-
0.8)E-07 erg/cm^2.

The time-averaged spectrum for the second emission episode, from
T0+39.9 to T0+60.4, is best fit by a Band function with Epeak = 320.7
+/- 35.7 keV, alpha = -0.9 +/- 0.1, and beta = -1.9 +/- 0.1. The event
fluence (10-1000 keV) in this time interval is (1.78 +/- 0.03)E-05.

The time-averaged spectrum for the third emission episode, from
T0+164.9 to T0+193.5, is best fit by a power law function with an
exponential high-energy cutoff. The power law index is -1.3 +/- 0.1
and the cutoff energy, parameterized as Epeak, is 205.2 +/- 42.8 keV.
The event fluence (10-1000 keV) in this time interval is(3.5 +/-
0.3)E-06 erg/cm^2.

The 1-sec peak photon flux measured starting from T0+49.6 s in the
10-1000 keV band is 19.5 +/- 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: GRB220305A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31690
SUBJECT: Correction to GCN 31689: Fermi GBM Report of GRB 220305A should be GRB 220305B
DATE:    22/03/06 00:27:22 GMT
FROM:    Adam Goldstein at Fermi-GBM, USRA  <adam.michael.goldstein@gmail.com>

R. Dunwoody (UCD), J. Mangan (UCD), and C.Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 11:33:20.48 UT on 05 March 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 220305B (trigger 668172805 / 220305481).

The on-ground calculated location, using the GBM trigger
data, is RA = 174, DEC = -34 (J2000 degrees,
equivalent to 11 h 36 m, -34 d 00 '), with a statistical uncertainty
of 1.5 degrees.

The angle from the Fermi LAT boresight at the GBM trigger time is 35
degrees.

The GBM light curve consists of three emission episodes, the most
prominent occurring around T0+50s, with a duration (T90) of about
172.8 s (50-300 keV).

The time-averaged spectrum for the first emission episode, from
T0-12.3 to T0+12.3, is best fit by a power law function with an
exponential high-energy cutoff. The power law index is -0.6 +/- 0.5
and the cutoff energy, parameterized as Epeak, is 60.9 +/- 9.1 keV.
The event fluence (10-1000 keV) in this time interval is (6.8 +/-
0.8)E-07 erg/cm^2.

The time-averaged spectrum for the second emission episode, from
T0+39.9 to T0+60.4, is best fit by a Band function with Epeak = 320.7
+/- 35.7 keV, alpha = -0.9 +/- 0.1, and beta = -1.9 +/- 0.1. The event
fluence (10-1000 keV) in this time interval is (1.78 +/- 0.03)E-05.

The time-averaged spectrum for the third emission episode, from
T0+164.9 to T0+193.5, is best fit by a power law function with an
exponential high-energy cutoff. The power law index is -1.3 +/- 0.1
and the cutoff energy, parameterized as Epeak, is 205.2 +/- 42.8 keV.
The event fluence (10-1000 keV) in this time interval is(3.5 +/-
0.3)E-06 erg/cm^2.

The 1-sec peak photon flux measured starting from T0+49.6 s in the
10-1000 keV band is 19.5 +/- 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: GRB220305A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31691
SUBJECT: Fermi GRB 220305A: Global MASTER-Net observations report 
DATE:    22/03/06 04:15:27 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, 
D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, T.Pogrosheva, E.Minkina,
A.Chasovnikov, V.Topolev, V.Grinshpun, D.Kuvshinov,  D. Cheryasov
(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. Gres, N.M. Budnev
(Irkutsk State University, API),

B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez,
M.L.H.Rodriguez (INAOE, OAGH)

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

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


MASTER-OAFA robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 220305A ( R. Dunwoody et al., GCN 31689) errorbox  56245 sec after notice time and 56274 sec after trigger time at 2022-03-06 03:11:15 UT, with upper limit up to  18.3 mag. The observations began at zenith distance = 25 deg. The sun  altitude  is -46.7 deg. 

The galactic latitude b = 26 deg., longitude l = 287 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1902853

We obtain a following upper limits.  

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

   56305 | 2022-03-06 03:11:15 |         MASTER-OAFA | (11h 29m 45.56s , -35d 27m 42.1s) |   C |    60 | 15.9 |        
   58403 | 2022-03-06 03:46:13 |         MASTER-OAFA | (11h 29m 45.60s , -35d 28m 47.3s) |   C |    60 | 18.3 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220306A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31693
SUBJECT: GRB 220306A: Fermi GBM Final Real-time Localization
DATE:    22/03/06 07:30:08 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 07:20:00 UT on 6 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220306A (trigger 668244005.521712 / 220306306).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 184.9, Dec = -30.0 (J2000 degrees, equivalent to J2000 12h 19m, -30d 00'), with a statistical uncertainty of 6.5 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/2022/bn220306306/quicklook/glg_skymap_all_bn220306306.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220306306/quicklook/glg_healpix_all_bn220306306.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220306306/quicklook/glg_lc_medres34_bn220306306.gif


GRB_name: GRB220306A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31694
SUBJECT: Fermi GRB 220306A: Global MASTER-Net observations report 
DATE:    22/03/06 07:45:26 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, 
D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, T.Pogrosheva, E.Minkina,
A.Chasovnikov, V.Topolev, V.Grinshpun, D.Kuvshinov,  D. Cheryasov
(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. Gres, N.M. Budnev
(Irkutsk State University, API),

B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez,
M.L.H.Rodriguez (INAOE, OAGH)

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

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


MASTER-OAGH robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) started inspect of the Fermi GRB 220306A ( Fermi GBM team, GCN 31693) errorbox  218 sec after notice time and 247 sec after trigger time at 2022-03-06 07:24:07 UT, with upper limit up to  18.6 mag. The observations began at zenith distance = 67 deg. The sun  altitude  is -64.7 deg. 

The galactic latitude b = 32 deg., longitude l = 295 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1903572

We obtain a following upper limits.  

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

     277 | 2022-03-06 07:24:07 |         MASTER-OAGH | (12h 43m 10.46s , -31d 06m 52.7s) |   C |    60 | 16.5 |        
     277 | 2022-03-06 07:24:07 |         MASTER-OAGH | (12h 43m 39.85s , -31d 28m 56.5s) |   C |    60 | 17.2 |        
     359 | 2022-03-06 07:25:29 |         MASTER-OAGH | (12h 25m 33.30s , -31d 06m 49.8s) |   C |    60 | 17.7 |        
     359 | 2022-03-06 07:25:29 |         MASTER-OAGH | (12h 26m 02.33s , -31d 28m 53.8s) |   C |    60 | 18.1 |        
     440 | 2022-03-06 07:26:50 |         MASTER-OAGH | (12h 32m 34.88s , -27d 17m 19.0s) |   C |    60 | 17.5 |        
     440 | 2022-03-06 07:26:50 |         MASTER-OAGH | (12h 33m 01.91s , -27d 39m 35.9s) |   C |    60 | 18.1 |        
     521 | 2022-03-06 07:28:11 |         MASTER-OAGH | (12h 41m 06.55s , -33d 00m 46.7s) |   C |    60 | 16.7 |        
     521 | 2022-03-06 07:28:11 |         MASTER-OAGH | (12h 41m 36.95s , -33d 22m 50.6s) |   C |    60 | 17.8 |        
     603 | 2022-03-06 07:29:33 |         MASTER-OAGH | (12h 23m 03.58s , -32d 59m 12.1s) |   C |    60 | 16.7 |        
     603 | 2022-03-06 07:29:33 |         MASTER-OAGH | (12h 23m 33.61s , -33d 21m 13.2s) |   C |    60 | 17.6 |        
     684 | 2022-03-06 07:30:54 |         MASTER-OAGH | (12h 15m 27.68s , -27d 18m 06.2s) |   C |    60 | 17.4 |        
     684 | 2022-03-06 07:30:54 |         MASTER-OAGH | (12h 15m 54.19s , -27d 40m 22.8s) |   C |    60 | 18.0 |        
     766 | 2022-03-06 07:32:16 |         MASTER-OAGH | (12h 11m 14.54s , -29d 11m 08.2s) |   C |    60 | 16.6 |        
     766 | 2022-03-06 07:32:16 |         MASTER-OAGH | (12h 11m 41.70s , -29d 33m 19.8s) |   C |    60 | 17.7 |        
     847 | 2022-03-06 07:33:37 |         MASTER-OAGH | (12h 20m 24.64s , -25d 24m 05.3s) |   C |    60 | 17.6 |        
     847 | 2022-03-06 07:33:37 |         MASTER-OAGH | (12h 20m 50.06s , -25d 46m 28.8s) |   C |    60 | 18.3 |        
     928 | 2022-03-06 07:34:58 |         MASTER-OAGH | (12h 04m 50.53s , -33d 01m 20.5s) |   C |    60 | 18.2 |        
     928 | 2022-03-06 07:34:58 |         MASTER-OAGH | (12h 05m 19.99s , -33d 23m 20.3s) |   C |    60 | 18.6 |        
    1009 | 2022-03-06 07:36:19 |         MASTER-OAGH | (11h 58m 26.46s , -27d 19m 12.1s) |   C |    60 | 17.5 |        
    1009 | 2022-03-06 07:36:19 |         MASTER-OAGH | (11h 58m 52.45s , -27d 41m 27.5s) |   C |    60 | 18.5 |        
    1091 | 2022-03-06 07:37:41 |         MASTER-OAGH | (12h 02m 43.18s , -34d 53m 45.0s) |   C |    60 | 17.4 |        
    1091 | 2022-03-06 07:37:41 |         MASTER-OAGH | (12h 03m 13.70s , -35d 15m 44.2s) |   C |    60 | 18.1 |        
    1172 | 2022-03-06 07:39:02 |         MASTER-OAGH | (12h 43m 13.89s , -31d 06m 55.7s) |   C |    60 | 18.0 |        
    1172 | 2022-03-06 07:39:02 |         MASTER-OAGH | (12h 43m 42.95s , -31d 29m 16.3s) |   C |    60 | 18.4 |        
    1253 | 2022-03-06 07:40:23 |         MASTER-OAGH | (12h 37m 12.99s , -25d 23m 18.3s) |   C |    60 | 17.4 |        
    1253 | 2022-03-06 07:40:23 |         MASTER-OAGH | (12h 37m 38.68s , -25d 45m 55.4s) |   C |    60 | 18.2 |        
    1335 | 2022-03-06 07:41:45 |         MASTER-OAGH | (12h 25m 27.29s , -31d 06m 12.6s) |   C |    60 | 17.6 |        
    1335 | 2022-03-06 07:41:45 |         MASTER-OAGH | (12h 25m 55.73s , -31d 28m 30.2s) |   C |    60 | 18.1 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220305A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31695
SUBJECT: GRB 220305A: Swift-XRT refined Analysis
DATE:    22/03/06 09:54:42 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

V. D'Elia (SSDC & INAF-OAR), A. D'Ai (INAF-IASFPA), J.A. Kennea (PSU),
A. Tohuvavohu (U. Toronto), B. Sbarufatti (PSU), J.P. Osborne (U.
Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), A.
Melandri (INAF-OAB) and R. Caputo report on behalf of the Swift-XRT
team:

We have analysed 6.2 ks of XRT data for GRB 220305A (Caputo et al. GCN
Circ. 31684), from 3.0 ks to 43.5 ks after the BAT trigger. The data
are entirely in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Beardmore et al. (GCN Circ. 31688).

The light curve can be modelled with a power-law decay with a decay
index of alpha=1.22 (+0.11, -0.10).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.34 (+0.28, -0.26). The
best-fitting absorption column is  8.3 (+2.0, -1.8) x 10^21 cm^-2, in
excess of the Galactic value of 2.6 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 3.8 x 10^-11 (9.1 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      8.3 (+2.0, -1.8) x 10^21 cm^-2
Galactic foreground: 2.6 x 10^21 cm^-2
Excess significance: 5.3 sigma
Photon index:      2.34 (+0.28, -0.26)

If the light curve continues to decay with a power-law decay index of
1.22, the count rate at T+24 hours will be 7.0 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.7 x
10^-13 (6.3 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01095215.

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


GRB_name: GRB220305A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31696
SUBJECT: Fermi GBM Sub-Threshold Detection of GRB 220305A
DATE:    22/03/06 16:47:37 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

J. Wood (NASA/MSFC) reports on behalf of the Fermi-GBM Team:

Swift-BAT detected GRB 220305A at 16:13:08 UT on 05 March, 2022 (Caputo
et al. GCN 31684). There was no Fermi-GBM onboard trigger around the
time of the event.
 
An automated, blind search for short gamma-ray bursts below the onboard
triggering threshold in Fermi-GBM identified no counterparts.

The GBM targeted search [1], the most sensitive, coherent search for
GRB-like signals identified a transient most significantly on the 8.192 s
timescale, with a location consistent with the Swift-BAT event and
a signal-to-noise ratio of 17.8, using the standard search protocol.
The GBM targeted search event was found with the highest
significance with a "normal" spectrum (Band function with
Epeak = 230 keV, alpha = -1.0, beta = -2.3) for a GRB.

This analysis is preliminary.

[1] Goldstein et al. 2019 arXiv:1903.12597

Note: Fermi-GBM also detected GRB 220305B at 11:33:20.48 UT on 05 March 2022
which was erroneously named GRB 220305A at the time of its initial publication
(GCN 31689, 31690). GRB 220305B is a different burst than the one
described here.


GRB_name: GRB220306B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31697
SUBJECT: GRB 220306B: Swift detection of a burst
DATE:    22/03/06 18:26:42 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

R. Caputo (GSFC), A. P. Beardmore (U Leicester), C. Gronwall (PSU),
J.D. Gropp (PSU), J. A. Kennea (PSU), A. Y. Lien (U Tampa),
F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester),
D. M. Palmer (LANL), T. M. Parsotan (GSFC/UMBC/CRESSTII),
M. H. Siegel (PSU) and A. Tohuvavohu (U Toronto) report on behalf of
the Neil Gehrels Swift Observatory Team:

At 18:15:37 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 220306B (trigger=1095288).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 5.378, +71.354 which is 
   RA(J2000) = 00h 21m 31s
   Dec(J2000) = +71d 21' 14"
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 ~2600 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 18:17:03.3 UT, 85.9 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 5.38628, 71.36313 which is equivalent
to:
   RA(J2000)  = 00h 21m 32.71s
   Dec(J2000) = +71d 21' 47.3"
with an uncertainty of 4.0 arcseconds (radius, 90% containment). This
location is 34 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. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 4.07
x 10^21 cm^-2 (Willingale et al. 2013). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 89 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 100% of
the XRT 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
XRT 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
0.578. 

Burst Advocate for this burst is R. Caputo (regina.caputo AT nasa.gov). 
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: GRB220305A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31698
SUBJECT: GRB 220305A: Swift-BAT refined analysis
DATE:    22/03/06 18:33:18 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@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),
R. Caputo (GSFC), 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 220305A (trigger #1095215)
(Caputo et al., GCN Circ. 31684).  The BAT ground-calculated position is
RA, Dec = 107.610, -37.703 deg which is
   RA(J2000)  =  07h 10m 26.4s
   Dec(J2000) = -37d 42' 09.2"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 25%.

The mask-weighted light curve shows a single-pulse structure that starts
at ~T-15 s, peaks at ~T0, and ends at ~T+11 s. The burst went out of the
BAT FOV at T+225.7 s. T90 (15-350 keV) is 21.12 +- 3.65 sec (estimated
error including systematics).

The time-averaged spectrum from T-15.04 to T+11.02 sec is best fit by
a simple power-law model.  The power law index of the time-averaged
spectrum is 1.66 +- 0.15.  The fluence in the 15-150 keV band is
2.0 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from
T-0.16 sec in the 15-150 keV band is 2.1 +- 0.5 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/1095215/BA/


GRB_name: GRB220306B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31699
SUBJECT: Swift GRB 220306B: Global MASTER-Net observations report 
DATE:    22/03/06 19:40:46 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, D. Vlasenko, 
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(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. Gres, N.M. Budnev
(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),

A. Gabovich, V.Yurkov 
(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) was pointed to the Swift GRB 220306B ( R. Caputo et al., GCN 31697) errorbox  3820 sec after notice time and 3846 sec after trigger time at 2022-03-06 19:19:44 UT, with upper limit up to  17.1 mag. The observations began at zenith distance = 55 deg. The sun  altitude  is -26.5 deg. 

MASTER-Kislovodsk robotic telescope  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the Swift GRB 220306B errorbox  4093 sec after notice time and 4118 sec after trigger time at 2022-03-06 19:24:16 UT, with upper limit up to  17.9 mag. The observations began at zenith distance = 61 deg. The sun  altitude  is -44.4 deg. 

The galactic latitude b =  9 deg., longitude l = 121 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1903942

We obtain a following upper limits.  

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

    3937 |         MASTER-Amur |   R |   180 | 17.1 |        
    4136 |         MASTER-Amur |   R |   180 | 17.1 |        
    4209 |   MASTER-Kislovodsk |   C |   180 | 17.6 |        
    4209 |   MASTER-Kislovodsk |   C |   180 | 14.5 |        
    4336 |         MASTER-Amur |   R |   180 | 17.1 |        
    4409 |   MASTER-Kislovodsk |   C |   180 | 12.5 |        
    4536 |         MASTER-Amur |   R |   180 | 17.0 |        
    4534 |   MASTER-Kislovodsk |   C |    30 | 16.9 |        
    4534 |   MASTER-Kislovodsk |   C |    30 | 14.3 |        
    4584 |   MASTER-Kislovodsk |   C |    30 | 16.8 |        
    4584 |   MASTER-Kislovodsk |   C |    30 | 14.5 |        
    4709 |   MASTER-Kislovodsk |   C |   180 | 17.9 |        
    4709 |   MASTER-Kislovodsk |   C |   180 | 14.6 |        
    4735 |         MASTER-Amur |   R |   180 | 17.0 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220306B
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31700
SUBJECT: GRB 220306B: Enhanced Swift-XRT position
DATE:    22/03/06 20:06:46 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 1203 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 220306B, 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 = 5.38792, +71.36361 which is equivalent
to:

RA (J2000): 00h 21m 33.10s
Dec (J2000): +71d 21' 49.0"

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: GRB220306B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31702
SUBJECT: GRB 220306B: Fermi GBM observation
DATE:    22/03/07 01:20:35 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

J. Wood (NASA/MSFC) reports on behalf of the Fermi GBM Team:

"At 18:15:36.24 UT on 06 March 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 220306B (trigger 668283341 / 220306761)
which was also detected by the Swift/BAT and Swift/XRT (Caputo et al. 2022, GCN 31697).
The GBM on-ground location is consistent with the Swift position.

The GBM light curve consists of a single pulse
with a duration (T90) of about 10.2 s (50-300 keV).
The time-averaged spectrum from T0-1.0 s to T0+9.2 s is
best fit by a Band function with Epeak = 160 +/- 122 keV,
alpha = -1.1 +/- 0.3, and beta = -1.8 +/- 0.2

The event fluence (10-1000 keV) in this time interval is
(1.7 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.2 s in the 10-1000 keV band
is 2.8 +/- 0.2 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: GRB220306B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31703
SUBJECT: GRB 220306B: Swift-XRT refined Analysis
DATE:    22/03/07 05:00:12 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A. D'Ai (INAF-IASFPA), A. Tohuvavohu (U. Toronto), B. Sbarufatti (PSU),
D.N. Burrows (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U.
Leicester), P.A. Evans (U. Leicester), A. Melandri (INAF-OAB), T.
Sbarrato (INAF-OAB) and R. Caputo report on behalf of the Swift-XRT
team:

We have analysed 6.6 ks of XRT data for GRB 220306B (Caputo et al. GCN
Circ. 31697), from 111 s to 24.3 ks after the  BAT trigger. The data
are entirely in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Evans et al. (GCN Circ. 31700).

The light curve can be modelled with a power-law decay with a decay
index of alpha=0.88 (+0.17, -0.12).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.80 (+0.32, -0.29). The
best-fitting absorption column is  7.1 (+2.9, -2.3) x 10^21 cm^-2, in
excess of the Galactic value of 4.1 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 4.9 x 10^-11 (7.6 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      7.1 (+2.9, -2.3) x 10^21 cm^-2
Galactic foreground: 4.1 x 10^21 cm^-2
Excess significance: 2.2 sigma
Photon index:      1.80 (+0.32, -0.29)

If the light curve continues to decay with a power-law decay index of
0.88, the count rate at T+24 hours will be 2.3 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.1 x
10^-13 (1.7 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01095288.

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


GRB_name: GRB220306B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31704
SUBJECT: GRB 220306B: BOOTES-1 optical upper limit
DATE:    22/03/07 15:18:18 GMT
FROM:    Youdong HU at IAA-CSIC  <huyoudong072@hotmail.com>

Y.-D. Hu, E. Fernandez-Garcia, T.-R. Sun, A. J. Castro-Tirado (IAA-CSIC),  C. Perez del Pulgar,  A. Castellon, I. Carrasco, A. Reina (Univ. de Malaga) and F. Rendon (IAA-CSIC and INTA-CEDEA) on behalf of a larger collaboration, report:

Following the detection of GRB 220306B by Swift (Caputo et al., GCNC 31697) and Fermi (Wood et al., GCNC 31702), the 0.3m BOOTES-1B robotic telescope in Mazagon (Huelva), southern Spain, automatically responded to this burst on Mar 7 at 00:05 UT (~5.8 hours after trigger). In the co-added frame (20 x 60 s, clear filter), no source is detected within the enhanced XRT position (Evans et al., GCNC 31700) down to 18.5 mag, which is consistent with the non-detections reported by UVOT (Caputo et al., GCNC 31697) and MASTER (Lipunov et al., GCNC 31699).

We thank the staff at INTA-CEDEA for their excellent support.


GRB_name: GRB220306B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31705
SUBJECT: GRB 220306B: AbAO optical observations, possible afterglow candidate
DATE:    22/03/07 15:44:23 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI),   A. Pozanenko (IKI), R. Ya. Inasaridze (AbAO), N. 
Pankov (HSE, IKI), D. Datashvili (AbAO), V. R. Ayvazian (AbAO),  G. V. 
Kapanadze (AbAO)  report on behalf of GRB IKI FuN:

We observed  the field of Swift GRB 220306B (Caputo et al. GCN 31697) 
which is also detected by GBM/Fermi (Wood  et al., GCN 31702) with AS-32 
telescope of Abastumani observatory (AbAO) in   R-filter starting on 
Mar. 06 (UT) 18:32:11. We  detected the  object at the edge (2.6 arcsec 
apart) of the enhanced XRT position (Evans et al. GCN 31700). The object 
is also presented in Pan-STARRS   as a red source (objID 
193630053894966412, r=21.42, i= 20.70, z=20.54). Due to non-optimal 
seeing we cannot discriminate a possible optical afterglow from the 
object.  Preliminary aperture photometry of the object is following

Date       UT start   t-T0    Filter Exp.    OT    Err.  UL(3sigma)
                       (mid, days)    (s)

2022-03-06 18:32:11    0.02886  R     50*60  19.98 0.12    22.7

The R magnitude of the object seems to be brighter than R_mag deduced 
for the object assuming the object is a star. We may suggest the 
afterglow superimposed of the object (Pan-STARRS  objID 
193630053894966412) and the red PanSTARRS  object could be a host galaxy 
of GRB 220306B.


GRB_name: GRB220306B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31707
SUBJECT: GRB 220306B: Swift-BAT refined analysis
DATE:    22/03/07 20:22:04 GMT
FROM:    Amy Lien at GSFC  <amy.y.lien@nasa.gov>

S. D. Barthelmy (GSFC), R. Caputo (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), 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 220306B (trigger #1095288)
(Caputo et al., GCN Circ. 31697).  The BAT ground-calculated position is
RA, Dec = 5.380, 71.384 deg which is
   RA(J2000)  =  00h 21m 31.3s
   Dec(J2000) = +71d 23' 04.1"
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 78%.

The mask-weighted light curve shows a single-peaked structure that starts
at ~T-2 s, peaks at ~T0, and ends at ~T+12 s. T90 (15-350 keV) is
12.34 +- 3.24 sec (estimated error including systematics).

The time-averaged spectrum from T-1.82 to T+11.66 sec is best fit by a
simple
power-law model.  The power law index of the time-averaged spectrum is
1.30 +- 0.20.  The fluence in the 15-150 keV band is 6.0 +- 0.7 x 10^-7
erg/cm2.
The 1-sec peak photon flux measured from T-0.05 sec in the 15-150 keV band
is 2.3 +- 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/1095288/BA/


GRB_name: GRB220304A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31710
SUBJECT: GRB 220304A Fermi GBM detection
DATE:    22/03/08 16:11:39 GMT
FROM:    Boyan A. Hristov at UAH  <bah0046@uah.edu>

Boyan A. Hristov (UAH) and C. Meegan (UAH) report on behalf of
the Fermi GBM Team:

"At 05:28:58.79 UT on 04 March 2022, the Fermi Gamma-Ray Burst
Monitor (GBM) triggered and located GRB 220304A (trigger
668064543 / 220304228, GCN 31672), which was also detected by
the Swift/BAT-GUANO (DeLaunay et al. 2022, GCN 31677).

The GBM light curve consists of a single spike with a duration
(T90) of about 32 s (50-300 keV).  The time-averaged spectrum
from T0+3.072 s to T0+35.841 s is best fit by a Band function
with Epeak = 90 +/- 2 keV, alpha = -0.24 +/- 0.06, and beta =
-3.2 +/- 0.1.  The event fluence (10-1000 keV) in this time
interval is (59 +/- 0.7)E-6 erg/cm^2.  The 1-sec peak photon
flux measured starting from T0+15.488 s in the 10-1000 keV band
is 36 +/- 1 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: GRB220306B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31711
SUBJECT: GRB 220306B: Tautenburg observations
DATE:    22/03/08 17:35:24 GMT
FROM:    Sylvio Klose at TLS Tautenburg  <klose@tls-tautenburg.de>

S. Klose, A. Nicuesa Guelbenzu, B. Stecklum, S. Melnikov, F. Ludwig (all 
TLS Tautenburg) report:

We observed the field of the Swift/Fermi GRB 220306B (Caputo et al., GCN 
31697; Wood et al., GCN 31782) with the Tautenburg 1.34m Schmidt telescope 
equipped with the TAUKAM 6kx6k CCD camera. Observations were performed on 
March 8, 2022, between 00:03 and 00:34 UT, about 30 hours after the burst.

Inside the enhanced XRT error circle (Evans et al., GCN 31700) we do not 
detect any source. Close to the error circle we detect two sources.

Source 1 lies at RA, DEC (J2000) = 00:21:33.42, +71:21:46.7 (+/- 0.5 
arcsec) and is located at the south-eastern border of the XRT error 
circle. For this source we measure the following AB magnitudes:

r = 21.33 +/- 0.16,
i = 20.67 +/- 0.10,
z = 20.28 +/- 0.16,

calibrated against the Pan-STARRS catalog.

This source was already detected and discussed by Belkin et al. (GCN 
31705). Our r-band data confirm that it is fading and that light from an 
underlying permanent object starts to dominate.

Source 2 lies at at RA, DEC (J2000) = 00:21:33.52, +71:21:51.9 and is 
located at the north-eastern border of the enhanced XRT error circle. For 
this source we measure r > 22.2 (3 sigma), i = 21.27 +/- 0.17, z = 20.83 
+/- 0.25. The nature of this source is uncertain; obviously it is 
unrelated to the GRB.


GRB_name: GRB220305B
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31713
SUBJECT: IPN triangulation of GRB 220305B
DATE:    22/03/08 21:15:37 GMT
FROM:    Anna Ridnaia at Ioffe Institute  <ridnaia@mail.ioffe.ru>

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

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

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

V. Savchenko, E. Bozzo, and C. Ferrigno,
on behalf of the INTEGRAL SPI-ACS GRB 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 220305B
(Fermi GBM observation: Dunwoody et al., GCN Circ. 31689)
has been detected by Fermi (GBM trigger 668172805), Konus-Wind,
INTEGRAL (SPI-ACS), and Mars-Odyssey (HEND), so far,
at about 41600 s UT (11:33:20).

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
 ---------------------------------------------
  RA(2000), deg                 Dec(2000), deg
 ---------------------------------------------
 Center:
  176.112 (11h 44m 27s) -32.550 (-32d 33' 01")
 Corners:
  180.687 (12h 02m 45s) -27.127 (-27d 07' 36")
  171.638 (11h 26m 33s) -36.980 (-36d 58' 48")
  171.416 (11h 25m 40s) -37.080 (-37d 04' 47")
  180.469 (12h 01m 53s) -27.299 (-27d 17' 57")
 ---------------------------------------------
The error box area is 2893 sq. arcmin, and its maximum
dimension is 12.7 deg (the minimum one is 4 arcmin).
The Sun distance was 137 deg.

This box may be improved.

The IPN localization is consistent with, but reduces the area of, the
Fermi GBM on-ground calculated location (GCN Circ. 31689).

A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB220305_T41651/IPN/

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


GRB_name: GRB220306B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31714
SUBJECT: GRB 220306B: Mondy optical observations, confirmation afterglow candidate
DATE:    22/03/08 22:01:09 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed  the field of Swift GRB 220306B (Caputo et al. GCN 31697)
which is also detected by GBM/Fermi (Wood  et al., GCN 31702) with 
AZT-33IK telescope of Mondy observatory  in   R-filter starting on
Mar. 07 (UT) 16:42:31. We  detected the  object (Belkin et al., GCN 
31705; Klose et al., GCN 31711) at the S-E edge of the enhanced XRT 
position (Evans et al. GCN 31700).   Due to non-optimal seeing we cannot 
discriminate a possible optical afterglow from the object.  Preliminary 
aperture photometry of the object is following

Date       UT start   t-T0    Filter Exp.    OT    Err.  UL(3sigma)
                        (mid, days)    (s)

2022-03-07 16:42:31   0.94924  R     20*120  21.20 0.22    22.0

The R magnitude of the object seems still to be brighter than R_mag 
deduced for the object assuming the object is a star. Taking into 
account results of  observations (Belkin et al., GCN 31705; this GCN) 
and Tautenburg observations (Klose et al., GCN 31711) we would more 
firmly suggest the object  is the afterglow of GRB 220306B. The object 
Pan-STARRS  objID  193630053894966412  could be a host galaxy of GRB 
220306B.


GRB_name: GRB220308A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31715
SUBJECT: IPN triangulation of GRB 220308A (long / very bright)
DATE:    22/03/08 22:36:37 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

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

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

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

and

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

The very bright, long-duration GRB 220308A
has been detected by Konus-Wind, INTEGRAL (SPI-ACS),
Fermi (GBM), Swift (BAT), and AGILE (MCAL),
so far, at about 20588 s UT (05:43:08).
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:
   356.500 (23h 46m 00s) +23.844 (+23d 50' 40")
  Corners:
   358.094 (23h 52m 23s) +22.701 (+22d 42' 02")
   355.336 (23h 41m 21s) +25.088 (+25d 05' 19")
   354.810 (23h 39m 15s) +24.953 (+24d 57' 11")
   357.591 (23h 50m 22s) +22.579 (+22d 34' 45")
  ---------------------------------------------
The error box area is 1.44 sq. deg, and its maximum
dimension is 3.75 deg (the minimum one is 25 arcmin).
The Sun distance was 30 deg.

This box may be improved.

A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB220308_T20585/IPN/

The time history and spectrum will be given in forthcoming
GCN Circulars.


GRB_name: GRB220308A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31716
SUBJECT: GRB 220308A: Swift/BAT-GUANO detection outside the coded FOV
DATE:    22/03/09 02:30:44 GMT
FROM:    Aaron Tohuvavohu at U Toronto  <aaron.tohu@gmail.com>

Aaron Tohuvavohu (U Toronto), James DeLaunay (UAlabama), Gayathri
Raman (PSU), Jamie A. Kennea (PSU), report:

Swift/BAT did not localize GRB 220308A onboard (T0: 2022-03-08T05:43:08
 UTC, INTEGRAL/SPI-ACS trig#9761, IPN GCN 31715).

The INTEGRAL 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 90 seconds of BAT event-mode data from
[-45,+45] 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,
arXiv:2111.01769), detects the burst with a sqrt(TS) of 97 in a 8.192
s analysis time bin.
The duration of this burst episode is ~10s.

NITRATES results indicate a burst coming from outside the coded FOV,
with DeltaLLHOut of -240. An out of FOV origin is consistent with the
IPN timing localization (GCN 31715).

See Section 9.1 and Figure 20 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: GRB220309A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31717
SUBJECT: GRB 220309A: Fermi GBM Final Real-time Localization
DATE:    22/03/09 06:15:02 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 06:04:43 UT on 9 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220309A (trigger 668498688.984364 / 220309253).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 147.0, Dec = -0.6 (J2000 degrees, equivalent to J2000 09h 48m, 0d 36'), with a statistical uncertainty of 11.5 degrees.

The angle from the Fermi LAT boresight is 59.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220309253/quicklook/glg_skymap_all_bn220309253.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220309253/quicklook/glg_healpix_all_bn220309253.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220309253/quicklook/glg_lc_medres34_bn220309253.gif


GRB_name: GRB220309A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31718
SUBJECT: Fermi GRB 220309A: Global MASTER-Net observations report 
DATE:    22/03/09 06:45:16 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, D. Vlasenko, 
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(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. Gres, N.M. Budnev
(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),

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


MASTER-OAFA robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 220309A ( Fermi GBM team, GCN 31717) errorbox  213 sec after notice time and 221 sec after trigger time at 2022-03-09 06:08:25 UT, with upper limit up to  18.5 mag. The observations began at zenith distance = 57 deg. The sun  altitude  is -49.3 deg. 

The galactic latitude b = 38 deg., longitude l = 238 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1905062

We obtain a following upper limits.  

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

     251 | 2022-03-09 06:08:25 |         MASTER-OAFA | (09h 00m 07.82s , -05d 38m 13.1s) |   C |    60 | 18.3 |        
     451 | 2022-03-09 06:11:44 |         MASTER-OAFA | (08h 58m 21.00s , -03d 42m 28.9s) |   C |    60 | 18.3 |        
     649 | 2022-03-09 06:15:03 |         MASTER-OAFA | (09h 02m 29.80s , -07d 32m 16.1s) |   C |    60 | 18.4 |        
     757 | 2022-03-09 06:16:50 |         MASTER-OAFA | (09h 49m 38.47s , +01d 59m 09.4s) |   C |    60 | 18.3 |        
     856 | 2022-03-09 06:18:30 |         MASTER-OAFA | (09h 57m 42.22s , +02d 00m 50.4s) |   C |    60 | 18.5 |        
     956 | 2022-03-09 06:20:09 |         MASTER-OAFA | (09h 49m 30.23s , +00d 06m 46.0s) |   C |    60 | 18.4 |        
    1057 | 2022-03-09 06:21:50 |         MASTER-OAFA | (09h 57m 37.25s , +00d 05m 55.5s) |   C |    60 | 18.3 |        
    1256 | 2022-03-09 06:25:10 |         MASTER-OAFA | (09h 00m 09.29s , -05d 38m 01.8s) |   C |    60 | 18.4 |        
    1456 | 2022-03-09 06:28:29 |         MASTER-OAFA | (08h 58m 24.29s , -03d 44m 13.4s) |   C |    60 | 18.3 |        
    1654 | 2022-03-09 06:31:48 |         MASTER-OAFA | (09h 02m 22.89s , -07d 31m 31.6s) |   C |    60 | 18.4 |        
    1754 | 2022-03-09 06:33:27 |         MASTER-OAFA | (09h 49m 34.41s , +02d 00m 41.6s) |   C |    60 | 18.2 |        
    1854 | 2022-03-09 06:35:07 |         MASTER-OAFA | (09h 57m 42.21s , +01d 59m 52.0s) |   C |    60 | 18.5 |        
    1953 | 2022-03-09 06:36:47 |         MASTER-OAFA | (09h 49m 30.51s , +00d 04m 42.6s) |   C |    60 | 18.2 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220308A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31719
SUBJECT: CALET Gamma-Ray Burst Monitor detection of GRB 220308A and its possible precursor
DATE:    22/03/09 09:01:19 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

P. S. Marrocchesi (U of Siena),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
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:

At 05:35:27.809 UTC on 8 March 2022, the CALET Gamma-ray Burst Monitor
(CGBM) triggered on a long weak GRB followed in ~460 s by the bright
GRB 220308A, localized by the IPN (Svinkin et al., GCN 31715;
https://gcn.gsfc.nasa.gov/other/220308A.gcn3).
Both bursts were seen by all CGBM detectors.
The first (trigger) burst might be a precursor of GRB 220308A.

The trigger burst light curve shows a double-peaked pulse which starts at
T+1.9 sec, peaks at T+3.6 sec,and ends at T+15.0 sec. The T90 and T50
durations measured by the SGM data are 11.6 +- 1.6 sec and 7.4 +- 1.6 sec
(40-1000 keV), respectively.
The GRB 220308A light curve shows a multi-peaked structure which starts
at T+461.6 sec, peaks at T+465.9 sec, and ends at T+481.9 sec.
The T90 and T50 durations measured by the SGM data are 15.4 +- 0.4 sec
and 4.0 +- 0.1 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1330752907/

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


GRB_name: GRB220308A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31723
SUBJECT: Konus-Wind detection of GRB 220308A
DATE:    22/03/09 22:19:58 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, D. Frederiks, M. Ulanov, A. Tsvetkova,
A. Lysenko, A. Ridnaia, and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration GRB 220308A
(IPN triangulation: Svinkin et al., GCN Circ. 31715;
Swift/BAT-GUANO detection: Tohuvavohu et al., GCN Circ. 31716;
CALET-CGBM detection: Marrocchesi et al., GCN Circ. 31719)
triggered Konus-Wind at T0=20585.134 s UT (05:43:05.134).

The burst light curve shows a multipeaked structure
which starts at ~T0-0.1 s and has a total duration of ~69 s.
The emission is seen up to ~15 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB220308_T20585/

As observed by Konus-Wind, the burst
had a fluence of 2.87(-0.11,+0.11)x10^-4 erg/cm2,
and a 64-ms peak flux, measured from T0+1.296 s,
of 1.06(-0.10,+0.10)x10^-4 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+22.016 s)
is best fit in the 20 keV - 16 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.93(-0.02,+0.02),
the high energy photon index beta = -3.42(-6.58,+0.47),
the peak energy Ep = 1099(-55,+57) keV
(chi2 = 130/97 dof).

The spectrum near the maximum count rate
(measured from T0+1.024 to T0+1.536 s)
is best fit in the 20 keV - 16 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.26(-0.09,+0.10),
the high energy photon index beta = -3.13(-1.01,+0.41),
the peak energy Ep = 1419(-150,+155) keV
(chi2 = 69/66 dof).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB220310A
Detection_method: MAXI Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31725
SUBJECT: GRB 220310A: MAXI/GSC detection
DATE:    22/03/10 01:24:33 GMT
FROM:    Motoko Serino at Aoyama Gakuin U.  <serino@phys.aoyama.ac.jp>

H. Negoro, M. Nakajima (Nihon U.), M. Serino (AGU), Y. Kawakubo (LSU),
K. Kobayashi, K. Asakura, K. Seino (Nihon U.),
T. Mihara, T. Tamagawa, J. Li, M. Matsuoka (RIKEN),
T. Sakamoto, S. Sugita, K. Komachi, H. Hiramatsu, A. Yoshida (AGU),
Y. Tsuboi, W. Iwakiri, H. Kawai, Y. Okamoto, S. Kitakoga, J. Kohara (Chuo U.),
M. Shidatsu, M. Iwasaki (Ehime U.),
N. Kawai, M. Niwano, R. Hosokawa, Y. Imai, N. Ito, Y. Takamatsu (Tokyo Tech),
S. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, M. Tominaga, T. Nagatsuka, M. Kurihara (JAXA),
Y. Ueda, S. Yamada, S. Ogawa, K. Setoguchi, T. Yoshitake, Y. Goto, R. Uematsu, K. Inaba (Kyoto U.),
H. Tsunemi (Osaka U.),
M. Yamauchi, Y. Nonaka, T. Sato, R. Hatsuda, R. Fukuoka (Miyazaki U.), T. Kawamuro (UDP/NAOJ),
K. Yamaoka (Nagoya U.),
M. Sugizaki (NAOC) 
report on behalf of the MAXI team:
The MAXI/GSC nova alert system triggered on a bright uncatalogued X-ray 
transient source at 2022-03-10T00:27:57 UT.
Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (168.612 deg, 23.451 deg) = (11 14 26, +23 27 03) (J2000)
with a 90% C.L. statistical error of 0.16 deg and an additional systematic 
uncertainty of 0.1 deg (90% containment radius).
Without assumptions on the source constancy, we obtain a rectangular error
box for the transient source with the following corners:
(168.038, 23.325) deg = (11 12 09, +23 19 29) (J2000)
(168.176, 23.093) deg = (11 12 42, +23 05 34) (J2000)
(169.335, 23.670) deg = (11 17 20, +23 40 12) (J2000)
(169.197, 23.903) deg = (11 16 47, +23 54 10) (J2000)
The X-ray flux averaged over the scan was 348 +- 37 mCrab
(4.0-10.0keV, 1 sigma error).
There was no significant excess flux in the previous transit at 3/9 22:55 UT
with an upper limit of 20 mCrab.


GRB_name: GRB220308B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31726
SUBJECT: GRB 220308B: Fermi GBM detection
DATE:    22/03/10 01:57:07 GMT
FROM:    Cori Fletcher at USRA  <cfletcher@usra.edu>

C. Fletcher (USRA), O. J. Roberts (USRA) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 05:35:30.10 UT on 08 March 2022, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 220308B (trigger 668410535 / 220308233).

The on-ground calculated location, using the GBM trigger
data, is RA = 292, DEC = 26 (J2000 degrees,
equivalent to 19 h 27 m, 26 d 26'), with a statistical uncertainty
of 5 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which we have characterized as a core-plus-tail model, with 90% of
GRBs having a 3.7 deg error and a small tail suffering a larger than 10 deg
systematic error. [Connaughton et al. 2015, ApJS, 216, 32] ).

The angle from the Fermi LAT boresight at the GBM trigger time is 78 degrees.

The GBM light curve consists of multiple peaks
with a duration (T90) of about 33 s (50-300 keV).
The time-averaged spectrum from T0+0.003 s to T0+32.769 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.0 +/- 0.1 and
the cutoff energy, parameterized as Epeak, is 342 +/- 93 keV,

The event fluence (10-1000 keV) in this time interval is
(4.4 +/- 0.5)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-0.512 s in the 10-1000 keV band
is 1.9 +/- 0.2 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/"
FSSC: Data  Data Access  GBM - Fermi Gamma-ray Space Telescope<https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/>
ID Name Description; GS-001: CTIME (daily version) The counts accumulated every 0.256 seconds in 8 energy channels for each of the 14 detectors. GS-002
fermi.gsfc.nasa.gov


GRB_name: GRB220310B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31727
SUBJECT: GRB 220310B: Fermi GBM Final Real-time Localization
DATE:    22/03/10 03:05:28 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 02:55:07 UT on 10 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220310B (trigger 668573712.866702 / 220310122).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 63.8, Dec = 69.6 (J2000 degrees, equivalent to J2000 04h 15m, 69d 35'), with a statistical uncertainty of 5.7 degrees.

The angle from the Fermi LAT boresight is 128.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220310122/quicklook/glg_skymap_all_bn220310122.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220310122/quicklook/glg_healpix_all_bn220310122.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220310122/quicklook/glg_lc_medres34_bn220310122.gif


GRB_name: GRB220310B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31728
SUBJECT: Fermi GRB 220310B: Global MASTER-Net observations report 
DATE:    22/03/10 03:15:26 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, D. Vlasenko, 
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(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. Gres, N.M. Budnev
(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),

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


MASTER-OAGH robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) started inspect of the Fermi GRB 220310B ( Fermi GBM team, GCN 31727) errorbox  553 sec after notice time and 582 sec after trigger time at 2022-03-10 03:04:50 UT, with upper limit up to  19.3 mag. The observations began at zenith distance = 45 deg. The sun  altitude  is -22.6 deg. 

The galactic latitude b = 14 deg., longitude l = 139 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1905827

We obtain a following upper limits.  

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

     642 | 2022-03-10 03:04:50 |         MASTER-OAGH | (04h 14m 41.43s , +69d 34m 27.5s) |   C |   120 | 18.8 |        
     642 | 2022-03-10 03:04:50 |         MASTER-OAGH | (04h 13m 44.40s , +69d 58m 56.3s) |   C |   120 | 19.0 |        
     793 | 2022-03-10 03:07:11 |         MASTER-OAGH | (04h 14m 40.88s , +69d 35m 33.4s) |   C |   140 | 18.8 |        
     793 | 2022-03-10 03:07:11 |         MASTER-OAGH | (04h 13m 43.73s , +70d 00m 01.8s) |   C |   140 | 19.1 |        
     970 | 2022-03-10 03:09:52 |         MASTER-OAGH | (04h 14m 48.31s , +69d 34m 34.1s) |   C |   170 | 18.9 |        
     970 | 2022-03-10 03:09:52 |         MASTER-OAGH | (04h 13m 51.11s , +69d 59m 04.3s) |   C |   170 | 19.3 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220310A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31730
SUBJECT: GRB 220310A: CALET Gamma-Ray Burst Monitor detection
DATE:    22/03/10 08:13:34 GMT
FROM:    Valentin Pal'shin at AGU  <val@phys.aoyama.ac.jp>

A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
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 220310A detected by MAXI/GSC (Negoro et al., GCN Circ. 31725)
triggered the CALET Gamma-ray Burst Monitor (CGBM) at 00:27:58.325 UTC
on 10 March 2022
(http://cgbm.calet.jp/cgbm_trigger/flight/1330907255/index.html).
The burst signal was seen by all CGBM detectors.

The burst light curve shows a multi-peaked structure which starts
at T+0.5 sec, peaks at T+33.6 sec,and ends at T+47.0 sec.
The T90 and T50 durations measured by the SGM data are 33.1 +- 8.3 sec
and 12.9 +- 1.2 sec (40-1000 keV), respectively.

The ground processed light curve is available at

http://cgbm.calet.jp/cgbm_trigger/ground/1330907255/

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


GRB_name: GRB220310A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31731
SUBJECT: GRB 220310A: Swift ToO observations
DATE:    22/03/10 08:37:40 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a ToO observation of the MAXI GRB 220310A. 
Automated analysis of the XRT data will be presented online at
https://www.swift.ac.uk/ToO_GRBs/00021482

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 MAXI 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: GRB220310A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31732
SUBJECT: GRB 220310A: MASTER optical counterpart detection
DATE:    22/03/10 10:09:01 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov (Lomonosov MSU), D.A.H.Buckley (SAAO),
V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, G.Antipov,
V.Senik, D.Kuvshinov, Ya.Kechin, Yu.Tselik (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),
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),
A. Gabovich, V.Yurkov (Blagoveschensk Educational State University)

MASTER Global Robotic Net (http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)
started MAXI GRB 220310A (Negoro et al. GCN 31725) observations in 
MASTER-OAFA , MASTEr-SAAO, MASTER-Kislovodsk, MASTER-OAGH (Lipunov et al. 31724)
see cover map and OT at https://master.sai.msu.ru/site/master2/observ.php?id=1905736

MASTER OT J111302.33+231508.0 discovery
MASTER-SAAO auto-detection system ( Lipunov et al., "MASTER Global Robotic Net", Advances in Astronomy, 2010, 30L )
  discovered GRB optical counterpart  at (RA, Dec) = 11h 13m 02.33s +23d 15m 08.0s at 2022-03-10.05882 UT.

The OT unfiltered magnitude at first image is 15.6m (mlim=19.5).
There is no minor planet at this place.

We have reference image on 2018-05-15.77649 UT with  unfiltered mlim=19.5m.

Spectral observations are required.


GRB_name: GRB220308A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31733
SUBJECT: GRB 220308A: AGILE detection
DATE:    22/03/10 14:05:01 GMT
FROM:    Alessandro Ursi at INAF/IAPS  <alessandro.ursi@gmail.com>

A. Ursi (INAF/IAPS), A. Di Piano (INAF/OAS-Bologna), F. Verrecchia, C.
Pittori (SSDC, and INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor
Vergata), A. Argan, M. Cardillo, C. Casentini, Y. Evangelista, E. Menegoni,
L. Foffano, G. Piano (INAF/IAPS), F. Lucarelli (SSDC, and INAF/OAR), A.
Bulgarelli, V. Fioretti, F. Fuschino, N. Parmiggiani (INAF/OAS-Bologna), M.
Marisaldi (INAF/OAS-Bologna, and Bergen University), M. Pilia, A. Trois
(INAF/OA-Cagliari), I. Donnarumma (ASI), F. Longo (Univ. Trieste and INFN
Trieste), A. Giuliani (INAF/IASF-Mi), report on behalf of the AGILE Team:

The AGILE satellite detected the long GRB 220308A at T0 = 2022-03-08
05:43:08 (UTC), reported by INTEGRAL/SPI-ACS (trig#9761), Fermi/GBM
(trigger no.668410535), CALET (GCN #31719), Konus-Wind (GCN #31723),
Swift/BAT (GCN #31716), and triangulated by IPN (GCN #31715).

The burst is clearly visible in the AGILE scientific ratemeters of the
SuperAGILE (SA; 20-60 keV), MiniCALorimeter (MCAL; 0.4-100 MeV), and
AntiCoincidence (AC; 50-200 keV) detectors. The event lasted about 22 s and
it released a total number of 2675 counts in the SA detector (above a
background rate of 140 Hz), 54840 counts in the MCAL detector (above a
background rate of 1300 Hz), and 104080 counts in the AC detector (above a
background rate of 3680 Hz). The AGILE ratemeter light curves can be found
at https://tools.ssdc.asi.it/ImgView/Agile/GRB220308A_AGILE_RM29 .

The event also triggered a partial high time resolution MCAL data
acquisition, covering the main peaks of the burst, from T1 = 2022-03-08
05:43:08.21 s +/- 0.01 (UTC) to T2 = 2022-03-08 05:43:15.06 +/- 0.01 s
(UTC), and released 16490 counts in the detector, above a background rate
of 640 Hz. The time-integrated spectrum of the burst in this time interval
can be fitted in the energy range 0.4-10 MeV with a Band function with
alpha = -0.70 (frozen), beta = -2.45 (-0.11/+0.09), and Epeak = 760
(-98/+97) keV, resulting in a reduced chi-squared of 1.32 (47 d.o.f.) and a
fluence of 1.4e-04 ergs/cm^2 (90% confidence level), in the same energy
range. The MCAL light curve can be found at:
https://tools.ssdc.asi.it/ImgView/Agile/077313_GRB_57380300810779330 .

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. Please
note that in the MCAL notice #573803008 the T0 was affected by a temporal
shift of about +19.5 sec due to episodic automated ground software problems
which are then corrected offline.


GRB_name: GRB220308A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31734
SUBJECT: Fermi GBM Detection of GRB 220308A
DATE:    22/03/10 20:42:33 GMT
FROM:    Cori Fletcher at USRA  <cfletcher@usra.edu>

C. Fletcher (USRA), O. J. Roberts (USRA) and J. Wood (NASA/MSFC) report on behalf of the Fermi-GBM Team:

Swift/BAT-GUANO detected GRB 220308A at 05:43:08 UT (GCN 31716), which was also detected by INTEGRAL/SPI-ACS (trig#9761), IPN (GCN 31715), Konus-Wind (GCN 31723), CGBM (GCN 31719), and AGILE (GCN 31733).

The GBM targeted search [1], the most sensitive, coherent search for GRB-like signals identified a transient most significantly on the 2.048 s consistent with GRB 220308A. The GBM targeted search location is RA=350.6, DEC = 4.7 (J2000 degrees, equivalent to 23 h 22 m, 04 d 42'), with an approximate 68% error radius of 10.6 degrees (statistical plus a core-plus-tail systematic model, with 77% of GRBs having a 2.4 deg error and the remaining fraction having a 10.9 deg error.)

The time-averaged spectrum (using a T0 of 2022-03-08T05:43:00 UT) from T0+8.000 s to T0+28.480 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is  -1.0 +/- 0.0 and the cutoff energy, parameterized as Epeak = 1371 +/- 26 keV. The event fluence (10-1000 keV) in this time interval is (1.53 +/- 0.05)E-04 erg/cm^2.

There was a Fermi-GBM onboard trigger of a gamma-ray burst (GRB 220308B, GCN 31726) approximately 460 s before  GRB 220308A, however, we do not believe these two events to be related.

The spectral analysis results presented above are preliminary.

[1] Goldstein et al. 2019 arXiv:1903.12597


GRB_name: GRB220310C
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31735
SUBJECT: GRB 220310C: Fermi GBM Final Real-time Localization
DATE:    22/03/10 22:34:09 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 22:23:51 UT on 10 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220310C (trigger 668643836.426778 / 220310933).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 290.7, Dec = 43.7 (J2000 degrees, equivalent to J2000 19h 22m, 43d 42'), with a statistical uncertainty of 5.4 degrees.

The angle from the Fermi LAT boresight is 27.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220310933/quicklook/glg_skymap_all_bn220310933.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220310933/quicklook/glg_healpix_all_bn220310933.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220310933/quicklook/glg_lc_medres34_bn220310933.gif


GRB_name: GRB220219B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31736
SUBJECT: ZTF22aabjpxh/AT2022cva (GRB 220219B): continued optical observations, possible photometric evidence of SN
DATE:    22/03/11 02:03:18 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI, HSE), A. Pozanenko (IKI), E. Klunko (ISTP),  A. 
Moskvitin (SAO RAS), R. Ya. Inasaridze (AbAO), N. Pankov (HSE), V. Kim 
(HSE, FAI), I. Reva (FAI), on behalf of GRB IKI FuN, and A. Rossi 
(INAF-OAS) report:

We are continuing observations of ZTF22aabjpxh/AT2022cva discovered by 
ZTF (Ho et al., GCN 31619) with AZT-33IK telescope of Mondy observatory, 
AS-32 telescope of Abastumani observatory, and Zeiss-1000  telescope of 
SAO RAS between 2022-02-24 and 2022-03-09. ZTF22aabjpxh/AT2022cva was 
observed in optic (Kim  et al., GCN 31628; Hu et al., GCN 31639; Belkin 
et al., GCNs 31643, 31683) and in X-ray by NICER (Pasham et al., GCN 
31635) and XRT/Swift (Beardmore et al., GCN 31644). 
ZTF22aabjpxh/AT2022cva is considered an afterglow of GRB 220219B (Ho et 
al., GCN 31619; Svinkin et al., GCN 31624; Tsvetkova et al., GCN 31646; 
Belkin et al., GCN 31683).

We clearly detect  the SDSS galaxy at z=0.293 (Fremling et al., GCN 
31629). Due to non-optimal seeing we could not  discriminate the 
afterglow from the galaxy. We use aperture  photometry of a source 
(afterglow + host  galaxy). Based on our  preliminary photometry we plot 
  a light curve  of the source, see an upper panel of the Figure in

http://grb.rssi.ru/GRB220219B/GRB220219B_AT2022cva_LC.png

To estimate power law index of the afterglow we fit our photometric data 
by a single power law + constant host galaxy flux between start of our 
observations and up to 13.4 days after GRB 220219B trigger. The host 
galaxy fit is R = 19.68+/-0.05 and PL index alpha = -1.75+/-0.4 (Belkin 
et al., GCN 31683). The light curve of the afterglow after subtraction 
of a flux of the host is presented at the bottom panel of the Figure in

http://grb.rssi.ru/GRB220219B/GRB220219B_AT2022cva_LC.png

Starting on ~15.5 days the light curve is rising above  afterglow 
approximation by the single power law and we consider it as a possible 
evidence of rising supernova.

We urge further spectroscopic and multicolour observations to confirm 
for SN associated with GRB 220219B.


GRB_name: GRB220306B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31737
SUBJECT: GRB 220306B: Nanshan/NEXT optical upper limit
DATE:    22/03/11 09:14:31 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

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

We observed the field of Swift GRB 220306B (Caputo et al., GCN 31697) 
using the NEXT-0.6m telescope located at Nanshan, Xinjiang, China. We 
obtained 3x40 s and 1x60 s frames in the Sloan r-band, starting at 
18:23:35 UT on 2022-03-06, i.e., 478 s after the BAT trigger.

No optical source is detected at the Enhanced Swift/XRT position (Evans 
et al., GCN 31700) in our stacked image, down to a limiting magnitude of 
r~19.3, calibrated with the nearby PanSTARRS field.


GRB_name: GRB220310A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31738
SUBJECT: GRB 220310A: GIT confirmation of optical afterglow.
DATE:    22/03/11 10:23:08 GMT
FROM:    Harsh Kumar at Indian Inst of Tech,Bombay  <harshkosli13@gmail.com>

H. Kumar (IITB), J. Stanzin (IAO), V. Bhalerao (IITB), G. C. Anupama (IIA),
S. Barway (IIA) report on behalf of the GIT team:

We observed GRB 220310A detected by MAXI/GSC H. Negoro et al., (GCN #31725)
and optical afterglow discovered by V. Lipunov (GCN #31732), with 0.7m
GROWTH-India Telescope (GIT). We obtained multiple 300-sec exposures in the
g',r' and i' filters. We clearly detected the afterglow in our stacked
image. The photometric results follow as:

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

 JD (mid) | T_mid-T0(days) | Filter | Magnitude (AB) |

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

2459649.085963 | 0.566 | g' | 19.86 +/- 0.03

2459649.093405 | 0.574 | r' | 19.45 +/- 0.04

2459649.100833 | 0.581 | i' | 19.11 +/- 0.04

2459649.327412 | 0.810 | g' | 20.66 +/- 0.08

2459649.334752 | 0.815 | r' | 20.21 +/- 0.07

2459649.342128 | 0.823 | i' | 19.70 +/- 0.09

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

On the basis of fading seen in our observations, we confirm the MASTER OT
J111302.33+231508.0 (GCN #31732) as an afterglow of GRB 220310A. Further,
using our r'-band data, we estimated the index of power-law decay index =
1.99 +/- 0.17. The magnitudes are calibrated against PanSTARRS DR1
(Chambers et al., 2016) and not corrected for Galactic extinction.


The GROWTH India Telescope (GIT) 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 operations of the telescope. Telescope technical
details are available at https://sites.google.com/view/growthindia/.


GRB_name: GRB220219B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31739
SUBJECT: ZTF22aabjpxh/AT2022cva (GRB 220219B): evidence of supernova in LBT spectra
DATE:    22/03/11 14:41:55 GMT
FROM:    Andrea Rossi at INAF  <andrea.rossi@inaf.it>

A. Rossi, E. Pian, F. Cusano, E. Maiorano, E. Palazzi (INAF-OAS) on 
behalf of the CIBO collaboration, and S. Belkin (IKI, HSE) report :

We report the results of the spectroscopic follow-up observations of 
ZTF22aabjpxh/AT2022cva, the afterglow of GRB 220219B (Ho et al., GCN 
31619; Kim  et al., GCN 31628; Hu et al., GCN 31639; Belkin et al., GCNs 
31643, 31683; Pasham et al., GCN 31635; Beardmore et al., GCN 31644; 
Tsvetkova et al., GCN 31646) at z=0.293 (Fremling et al., GCN 31629). 
The optical spectra were obtained with the Multi-Object Double 
Spectrographs (MODS) instrument mounted on the 2x8.4-m LBT telescope 
(Mt. Graham, AZ, USA) at ~11 UT on 2021-03-07, ~16 days (i.e. ~12 
rest-frame days) after the burst trigger. The spectra covers the 
wavelength range 3200-10000 AA, and we obtained a total of 6 exposures 
of 900s. The resulting spectrum has been corrected for Galactic 
extinction (A_V = 0.025 mag).

The slit was place in order to cover both the host galaxy and the GRB 
position. In addition to the host spectra, a second trace is well 
visible in the 2D image of the spectrum although superimposed to the one 
of the host galaxy. Its low S/N extracted spectrum shows features 
similar to those exhibited by XRF-associated SN2006aj at a similar phase 
(Mazzali et al. 2006, Nature, 442, 1018). This confirms the bump 
observed by Belkin et al. (GCN 31736) as due to the emerging 
contribution of the SN.

We acknowledge the excellent support from the LBTO, in particular B. 
Rothberg and J. Williams, and from the LBT-INAF, particularly E. Marini 
in obtaining these observations.


GRB_name: GRB220311A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31740
SUBJECT: GRB 220311A: Fermi GBM Final Real-time Localization
DATE:    22/03/11 16:43:54 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 16:33:18 UT on 11 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220311A (trigger 668709203.400826 / 220311690).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 131.1, Dec = 55.0 (J2000 degrees, equivalent to J2000 08h 44m, 55d 00'), with a statistical uncertainty of 18.6 degrees.

The angle from the Fermi LAT boresight is 111.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220311690/quicklook/glg_skymap_all_bn220311690.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220311690/quicklook/glg_healpix_all_bn220311690.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220311690/quicklook/glg_lc_medres34_bn220311690.gif


GRB_name: GRB220311A
Detection_method: INTEGRAL
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31744
SUBJECT: GRB 220311A: A long GRB detected by INTEGRAL
DATE:    22/03/11 17:24:07 GMT
FROM:    Sandro Mereghetti at IASF-Milano/INAF  <sandro.mereghetti@inaf.it>

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 gamma ray burst lasting about 20 s has been detected by IBAS in the
 IBIS/ISGRI data at 16:33:10  UT of March 11, 2022.

The refined coordinates (J2000) are:
R.A.=  157.9747 deg
DEC.=  +66.0819 deg
with an uncertainty of 3  arcmin (90% c.l.).

The burst had a peak flux of 0.3 ph/cm2/s (20-200 keV, 1-s integration
time) and a fluence in the same energy range of about 2e-7  erg/cmq.

A plot of the light curve will  be posted at
http://ibas.iasf-milano.inaf.it/IBAS_Results.html

--


GRB_name: GRB220311A
Detection_method: retraction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31745
SUBJECT: GRB 220311A: MASTER OT retraction
DATE:    22/03/11 19:50:59 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov (Lomonosov MSU)

The published OT candidate (GCN Circ 31741) is the noise inside the 
errorbox of one of the invalid triggers.

I'm sorry for the problems.


GRB_name: GRB220310C
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31746
SUBJECT: GRB 220310C: Swift/BAT-GUANO candidate arcminute localization
DATE:    22/03/11 20:30:38 GMT
FROM:    Aaron Tohuvavohu at U Toronto  <aaron.tohu@gmail.com>

Aaron Tohuvavohu (U Toronto), James DeLaunay (UAlabama), Gayathri
Raman (PSU), Jamie A. Kennea (PSU), report:

Swift/BAT did not localize GRB 220310C onboard (T0:
2022-03-10T22:23:51 UTC, Fermi/GBM GCN 31735).

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,
arXiv:2111.01769), detects the burst in a 8.192 s analysis time bin
with a sqrt(TS) of 9.7.
A candidate arcminute localization is found with DeltaLLHOut of 19.7
and a DeltaLLHPeak of 5.7.

For this reason we can confidently claim detection, and preference for
an in FOV origin, but the best fit arcmin localization is not strongly
preferred over other positions.
A few burst locations with comparable DeltaLLHPeak have been
previously verified with afterglow discovery (eg GRB 211106A).

See Section 9.1 and Figure 20 in the NITRATES paper for brief
descriptions and interpretations of sqrt(TS), DeltaLLHPeak, and
DeltaLLHOut.

No source is found with conventional BAT imaging. This is expected
given the strength of the signal in BAT, and its position near the
edge of the coded FOV.

The BAT position is
RA, Dec = 290.069, +40.253 deg which is
   RA(J2000)  = 19h 20m 16.62s
   Dec(J2000) = +40d 15â€² 12.3â€³
with an estimated uncertainty of 5 arcmin.

This independent position is consistent with the Fermi/GBM
localization (GCN 31735).

XRT and UVOT follow-up has been requested.
Results of follow-up observations will be reported in future circulars.

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: GRB220310C
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31747
SUBJECT: GRB 220310C: Swift ToO observations
DATE:    22/03/12 02:57:35 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a ToO observation of the Swift/BAT-GUANO GRB 220310C. 
Automated analysis of the XRT data will be presented online at
https://www.swift.ac.uk/ToO_GRBs/00021483

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 Swift/BAT-GUANO 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: GRB220310A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31748
SUBJECT: Konus-Wind detection of GRB 220310A
DATE:    22/03/12 08:25:44 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

D. Svinkin, D. Frederiks, M. Ulanov, A. Tsvetkova,
A. Lysenko, A. Ridnaia, and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration GRB 220310A
(MAXI/GSC detection: Negoro et al., GCN Circ. 31725;
CALET-CGBM detection: Negoro et al., GCN Circ. 31730)
triggered Konus-Wind at T0=1702.557 s UT (00:28:22.557).

The burst light curve shows an initial weak episode
which starts at ~T0-24 s and ends at ~T0-12 s,
followed by a brighter multipeaked structure
seen up to ~T0+37 s. The total burst duration is ~61 s.
The emission is seen up to ~7 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB220310_T01702/

As observed by Konus-Wind, the burst
had a fluence of 3.15(-0.46,+0.54)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+14.144 s,
of 2.32(-0.62,+0.62)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+41.216 s)
is best fit in the 20 keV - 8 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.49(-0.37,+0.61),
the high energy photon index beta = -2.47(-0.67,+0.25),
the peak energy Ep = 138(-27,+32) keV
(chi2 = 75/85 dof).

The spectrum near the maximum count rate
(measured from T0+8.448 s to T0+16.640 s)
is best fit in the 20 keV - 8 MeV range
by a power law with exponential cutoff model:
with  alpha = -0.70(-0.24,+0.28)
and Ep = 168(-18,+23) keV (chi2 = 67/75 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.5
(chi2 = 67/74 dof).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB220310C
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31749
SUBJECT: GRB 220310C: Swift-XRT observations
DATE:    22/03/12 22:45:55 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

D.N. Burrows (PSU), J. D. Gropp (PSU), J.P. Osborne (U. Leicester),
K.L. Page (U. Leicester), T. Sbarrato (INAF-OAB), P. D'Avanzo
(INAF-OAB), M.G. Bernardini (INAF-OAB), J.A. Kennea (PSU) and P.A.
Evans (U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the
Swift/BAT-GUANO-detected burst GRB 220310C, collecting 4.6 ks of Photon
Counting (PC) mode data between T0+102.8 ks and T0+120.2 ks. 

Four uncatalogued X-ray sources have been detected, however none of
them is above the RASS limit or shows definitive signs of fading.
Therefore, at the present time we cannot identify which, if any, is the
afterglow. Details of these sources are given below:

Source 1:
  RA (J2000):  289.9580  =  19:19:49.91
  Dec (J2000): +40.2093  =  +40:12:33.3
  Error: 7.9 arcsec (radius, 90% conf. [Enhanced position])
  Count-rate: (4.4 +/- 1.2)e-3 ct s^-1  
  Distance: 344 arcsec from Swift/BAT-GUANO position.
  Flux: (9.6 +/- 2.7)e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV)

Source 2:
  RA (J2000):  290.2354  =  19:20:56.50
  Dec (J2000): +40.3333  =  +40:19:59.9
  Error: 7.6 arcsec (radius, 90% conf.)
  Count-rate: (3.7 [+1.4, -1.1])e-3 ct s^-1   
  Distance: 539 arcsec from Swift/BAT-GUANO position.
  Flux: (1.39 [+0.51, -0.42])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)

Source 3:
  RA (J2000):  290.1544  =  19:20:37.05
  Dec (J2000): +40.2064  =  +40:12:23.0
  Error: 6.3 arcsec (radius, 90% conf.)
  Count-rate: (1.92 [+0.98, -0.76])e-3 ct s^-1  
  Distance: 288 arcsec from Swift/BAT-GUANO position.
  Flux: (4.2 [+2.2, -1.7])e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV)

Source 4:
  RA (J2000):  289.8727  =  19:19:29.46
  Dec (J2000): +40.2572  =  +40:15:26.0
  Error: 6.4 arcsec (radius, 90% conf.)
  Count-rate: (1.41 [+0.96, -0.69])e-3 ct s^-1  
  Distance: 540 arcsec from Swift/BAT-GUANO position.

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/00021483.

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


GRB_name: GRB220310A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31750
SUBJECT: GRB 220310A: [KAO-Egypt] SDSS r, i observation
DATE:    22/03/13 08:17:39 GMT
FROM:    Ahmed Fouad at NRIAG  <ahmed.fouad@nriag.sci.eg>

Ahmed M. Fouad, Ali Takey, Mona Molham, Saad Ata, Ola Ali (NRIAG)
report:

We observed the optical counterpart of GRB 220310A
(H. Negoro et al., GCN 31725)
using a 1.88-m telescope at the Kottamia Astronomical Observatory (KAO),
NRIAG, Egypt.

The source was visible at the position discovered by
(V. Lipunov et al., GCN 31732)
where the SDSS galaxy (ObjID: 1237667910586532614) is located.
KAO observations started from 22:05:22 to 23:06:00 UT on 10-03-2022,
~ 21.5 hrs after the MAXI/GSC trigger.
The combined images of 10 x 150sec were created for SDSS r,i images.

We report the preliminary photometry as:
--------------------------------------------------------
Object                           / r-mag    / r-err     / i-mag     / i-err
-------------------------------/------------/-----------/------------/---------
GRB220310A by KAO  / 19.723  / 0.141   / 19.727  / 0.090
Published SDSS-gal.   / 21.94     / 0.19    / 21.62     / 0.22
-------------------------------------------------------------------------------

Aperture photometry was done based on 9 stars around the GRB in
a FoV = 8' x 8', selected from the SDSS-DR16.

The magnitude is not corrected for Galactic extinction
in the direction of the GRB.


GRB_name: GRB220310A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31751
SUBJECT: GRB 220310A: K-800 of Terskol observatory optical upper limit
DATE:    22/03/13 10:30:02 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed GRB 220310A (Negoro  et al., GCN 31725; Yoshida et al., GCN 
31730; Svinkin et al., GCN 31748) with K-800 telescope  of Terskol 
observatory starting on Mar. 12 (UTC) 21:34:44. We do not detect the 
optical afterglow (Lipunov et al., GCN 31732;  Kumar et al., GCN 31738; 
Fouad et al., GCN 31750).    Preliminary photometry of the field in 
Clear filter is following


Date       UT start t-T0    Filter     Exp. OT    Err  UL(3sigma)

2022-03-12 21:34:44 2.89151  Clear    68*30  n/d  n/d  20.8


The photometry is based on the nearby SDSS-DR12 stars R (Lupton
transformations)
R.A. Dec R
11:13:05.99760 +23:17:03.0084 16.852
11:12:35.64984 +23:13:33.4308 16.911


GRB_name: GRB201021C
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31752
SUBJECT: GRB 201021C: TAROT Reunion observatory optical light curve
DATE:    22/03/13 22:08:20 GMT
FROM:    Alain Klotz at IRAP-CNRS-OMP  <Alain.Klotz@free.fr>

A. Klotz (CNRS-OMP-IRAP),
M. Fortune, R. Augerai (Universite de la Renuion),
P. Thierry  (AGORA),
L. Eymar, S. Antier, M. Boer, A. de Ugarte Postigo (CNRS-OCA-ARTEMIS),

We analyzed archive images of the SWIFT trigger 1001130 (GRB 201021C,
BAT detection by  Lien et al. GCN Circ. 28730,
early optical ground observations by Lipunov et al. GCN Circ. 28733,
redshift by Vielfaure et al. GCN Circ. 28739)
with the TAROT robotic telescope (D=18cm) located
at Les Makes Observatory, Reunion Island, France.

Images were acquired without any filter, camera FLI PL16803
and Takahashi Epsilon 180ED.

According the reference star NOMAD-1 0340-0006028 R=13.85
we give the photometry of the GRB optical transient:

  t1(s) t2(s)     R  dmag
    813   993 15.92  0.04
   1003  1183 16.02  0.03
   1190  1370 16.24  0.05
   1388  1568 16.28  0.04
   1575  1755 16.52  0.06
   1762  1942 16.62  0.06
   2048  2228 16.80  0.08
   2236  2416 16.92  0.09
   2425  3178 17.12  0.06
   3198  4132 17.54  0.09
   4139  9462 17.82  0.10

t1 and t2 are start and stop acquisition since the trigger.

Magnitudes are not corrected for Galactic dust extinction.


GRB_name: GRB210222B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31753
SUBJECT: GRB 210222B: TAROT Reunion observatory optical light curve
DATE:    22/03/13 22:11:11 GMT
FROM:    Alain Klotz at IRAP-CNRS-OMP  <Alain.Klotz@free.fr>

A. Klotz (CNRS-OMP-IRAP),
M. Fortune, R. Augerai (Universite de la Renuion),
P. Thierry  (AGORA),
L. Eymar, S. Antier, M. Boer, A. de Ugarte Postigo (CNRS-OCA-ARTEMIS),

We analyzed archive images of the SWIFT trigger 1034325 (GRB 210222B,
BAT detection by Gropp et al. GCN Circ. 29545,
early optical ground observations by Fernandez-Garcia et al. GCN Circ. 
29546,
redshift by Agui Fernandez et al. GCN Circ. 29552)
with the TAROT robotic telescope (D=18cm) located
at Les Makes Observatory, Reunion Island, France.

Images were acquired without any filter, camera FLI PL16803
and Takahashi Epsilon 180ED.

According the reference star NOMAD-1 0750-0237314 R=15.43
we give the photometry of the GRB optical transient:

t1(s) t2(s)     R  dmag
   342   433 15.76  0.06
   439   529 16.08  0.07
   536   626 16.14  0.08
   658   748 16.28  0.09
   755   845 16.38  0.09
   853   942 16.38  0.09
  1526  1706 16.98  0.12
  1714  1894 17.28  0.15
  1902  2543 17.32  0.13
  2550  3317 17.74  0.21
  3347  4843 17.92  0.25
  4852  6755 18.52  0.47

t1 and t2 are start and stop acquisition since the trigger.

Magnitudes are not corrected for Galactic dust extinction.


GRB_name: GRB210722A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31754
SUBJECT: GRB 210722A: TAROT Reunion observatory optical light curve
DATE:    22/03/13 22:11:59 GMT
FROM:    Alain Klotz at IRAP-CNRS-OMP  <Alain.Klotz@free.fr>

A. Klotz (CNRS-OMP-IRAP),
M. Fortune, R. Augerai (Universite de la Renuion),
P. Thierry  (AGORA),
L. Eymar, S. Antier, M. Boer, A. de Ugarte Postigo (CNRS-OCA-ARTEMIS),

We analyzed archive images of the SWIFT trigger 1061223 (GRB 210722A,
BAT detection by D'Avanzo et al. GCN Circ. 30475,
early optical ground observations by Zhu et al. GCN Circ. 30476,
redshift by Thoene et al. GCN Circ. 30487)
with the TAROT robotic telescope (D=18cm) located
at Les Makes Observatory, Reunion Island, France.

Images were acquired without any filter, camera FLI PL16803
and Takahashi Epsilon 180ED.

According the reference star NOMAD-1 0836-0016935 R=12.57
we give the photometry of the GRB optical transient:

t1(s) t2(s)     R  dmag
  2170  2935 16.08  0.16
  2944  4067 16.24  0.12
  4074  4653 16.78  0.14
  4659  5238 16.60  0.14
  5244  6744 17.04  0.22

t1 and t2 are start and stop acquisition since the trigger.

Magnitudes are not corrected for Galactic dust extinction.


GRB_name: GRB220310C
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31755
SUBJECT: GRB 220310C: Fermi GBM observation
DATE:    22/03/14 02:11:55 GMT
FROM:    Peter Veres at UAH  <veresp@gmail.com>

P. Veres and C. Meegan (both UAH)
report on behalf of the Fermi GBM Team:

"At 22:23:51.43 UT on 10 March 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 220310C (trigger 668643836 / 220310933)
which was also detected by the Swift/BAT (Tohuvavohu et al., GCN 31746).
The Fermi GBM Final Real-time Localization (GCN 31735) is consistent
with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 30 degrees.

The GBM light curve shows a single peak
with a duration (T90) of about 16.4 s (50-300 keV).
The time-averaged spectrum from T0-6.1 s to T0+16.4 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.74 +/- 0.30 and
the cutoff energy, parameterized as Epeak, is 180 +/- 51 keV.

The event fluence (10-1000 keV) in this time interval is
(1.52 +/- 0.27)E-6 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-1.7 s in the 10-1000 keV band
is 1.28 +/- 0.18 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: GRB220310A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31756
SUBJECT: IPN triangulation of GRB 220310A
DATE:    22/03/14 21:25:39 GMT
FROM:    Anna Ridnaia at Ioffe Institute  <ridnaia@mail.ioffe.ru>

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

A. Ridnaia, D. Frederiks, D. Svinkin, A. Lysenko,
and T. Cline on behalf of the Konus-Wind 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 220310A
(MAXI/GSC detection: Negoro et al., GCN Circ. 31725;
CALET-CGBM detection: Yoshida et al., GCN Circ. 31730;
Konus-Wind detection: Svinkin et al., GCN Circ. 31748)
was detected by MAXI(GSC), CALET (GBM), Konus-Wind,
and Mars-Odyssey (HEND) at about 1702 s UT (00:28:22).

We have triangulated it to a Konus-HEND annulus centered at
RA(2000)=124.878 deg (08h 19m 31s)  Dec(2000)=+20.557 deg (+20d 33' 25"),
whose radius is 40.183 +/- 0.041 deg (3 sigma).

The MAXI/GSC localization is consistent with the annulus.

The position of the optical transient J111302.33+231508.0
(Lipunov et al., GCN Circ. 31732) is inside the annulus at 0.7 arcmin
from its center line.

The positional and temporal coincidence of this burst with the OT
supports the conclusion that the OT is the GRB counterpart.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB220310_T01702/IPN


GRB_name: GRB220311A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31757
SUBJECT: GRB 220311A: MITSuME Akeno optical upper limits
DATE:    22/03/15 02:22:55 GMT
FROM:    Ryohei Hosokawa at Tokyo Institute of Technology  <hosokawa@hp.phys.titech.ac.jp>

R. Hosokawa, Y. Imai, R. Yamaguchi, K. L. Murata, M. Niwano, N. Ito,
Y. Takamatsu, R. Noto, S. Sato, M. Takaku, Y. Yatsu, and N. Kawai
(Tokyo Tech) report on behalf of the MITSuME collaboration:

We observed the field of GRB 220311A (The Fermi GBM team GCN Circular
#31740, V. Yurkov et al. GCN Circular #31741, V. Lipunov et al. GCN
Circular #31742, V. Lipunov et al. GCN Circular #31743, S.Mereghetti
et al. GCN Circular #31744, V. Lipunov et al. GCN Circular #31745)
with the optical three color (g', Rc, and Ic) CCD cameras attached to
the MITSuME 50 cm telescope Akeno. The observation with a series of 60
sec exposures started at 2022-03-11 16:44:51 UT (11.7 minutes after
IBAS trigger). We stacked the images with good conditions. We did not
detect any uncatalogued sources within the IBAS error region
(S.Mereghetti et al. GCN Circular #31744). We obtained the 5-sigma
limits of the stacked images as follows.

T0+[min] MID-UT T-EXP[sec] 5-sigma limits
------------------------------------------------------------------------------------------------
29.0 2022-03-11 17:02:10 1440 g'>19.8, Rc>19.8, Ic>19.0
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time

We used PS1 catalog for flux calibration.
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: GRB220315A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31758
SUBJECT: GRB 220315A: Fermi GBM Final Real-time Localization
DATE:    22/03/15 02:37:20 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 02:25:56 UT on 15 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220315A (trigger 669003961.874798 / 220315101).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 236.1, Dec = -76.8 (J2000 degrees, equivalent to J2000 15h 44m, -76d 47'), with a statistical uncertainty of 3.5 degrees.

The angle from the Fermi LAT boresight is 21.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220315101/quicklook/glg_skymap_all_bn220315101.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220315101/quicklook/glg_healpix_all_bn220315101.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220315101/quicklook/glg_lc_medres34_bn220315101.gif


GRB_name: GRB220306B
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31759
SUBJECT: GRB 220306B: Swift/UVOT Upper Limits
DATE:    22/03/15 13:10:24 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <mhs18@psu.edu>

M. H. Siegel (PSU) and Caputo (GSFC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 220306B
89 s after the BAT trigger (Caputo et al., GCN Circ. 31697).
No optical afterglow consistent with the XRT position (Evans et al. GCN Circ. 31700)
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            89          239          147         >19.9
u_FC               302          552          246         >20.1
white               89         1716          402         >20.4
v                  631         1601          117         >18.7
b                  557         1701          117         >19.9
u                  302         1676          343         >20.2
w1                 680         1650          117         >19.3
m2                 656         1626          117         >19.4
w2                 607         5204          213         >19.4

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.578 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB220311A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31760
SUBJECT: GRB 220311A: Fermi GBM observation
DATE:    22/03/15 14:57:05 GMT
FROM:    Rachel Hamburg at UAH  <rkh0007@uah.edu>

R. Hamburg (UAH) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 16:33:18.40 UT on 11 March 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 220311A (trigger 668709203 / 220311690), which
was also detected by the INTEGRAL/IBAS (Mereghetti et al. 2022, GCN 31740).
The Fermi GBM Final Real-time Localization (GCN 31744) is largely
consistent with the INTEGRAL position.

The angle from the Fermi LAT boresight at the GBM trigger time is 111
degrees.

The GBM light curve shows a single spike with a duration (T90) of about
10 s (50-300 keV). The time-averaged spectrum from
T0-5.1 s to T0+0.0 s is adequately a simple power law function with index
-1.55 +/- 0.11.

The event fluence (10-1000 keV) in this time interval is
(1.8 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-4.7 s in the 10-1000 keV band
is 1.8 +/- 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: GRB220315A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31761
SUBJECT: GRB 220315A: MASTER Global Robotic Net optical observations
DATE:    22/03/15 23:08:26 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, D.Vlasenko, G.Antipov,
V.Senik, D.Kuvshinov, Ya.Kechin, Yu.Tselik (Lomonosov Moscow State University, SAI, Physics Department),
C.Francile, R. Podesta, C.Lopez, F. Podesta (Observatorio Astronomico Felix Aguilar OAFA),
D.A.H.Buckley (SAAO),
R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, 
A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory),
N.M.Budnev, O.A.Gress (ISU,API),
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, vol. 2010, 30L)
started Fermi GRB 220315A (Fermi GBM team GCN 31758, Ttrigger= 2022-03-15 02:25:56 UT) alert observations at 
MASTER-OAFA robotic telescope, located in Argentina (OAFA observatory of San Juan National University)
  518 sec after notice time (549 sec after trigger time) at 2022-03-15 02:35:05 UT, with upper limit up to  17.8 mag. 
The observations began at zenith distance = 61 deg. The sun  altitude was -44.7 deg.
The galactic latitude b = -18 deg.,longitude l = 313 deg.

MASTER-SAAO started observations just after sunset at 2022-03-15 17:39:36UT with  upper limits 17.0 mag at first image.
The observations began at 23deg altitude, the sun altitude was -10deg.

Real time updated cover map and OT, that can be discovered, will be available here:
https://master.sai.msu.ru/site/master2/observ.php?id=1911047

We obtained the following upper limits at first images
Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
      619 | 2022-03-15 02:35:05 |         MASTER-OAFA | (15h 42m 55.34s , -77d 27m 34.1s) |   C |   140 | 17.7 |
      814 | 2022-03-15 02:38:05 |         MASTER-OAFA | (15h 43m 03.16s , -77d 27m 05.3s) |   C |   170 | 17.8 |
Filter C is a clear (unfiltred) band.


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


GRB_name: GRB220317A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31763
SUBJECT: GRB 220317A: Fermi GBM Final Real-time Localization
DATE:    22/03/17 12:58:50 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 12:48:30 UT on 17 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220317A (trigger 669214115.664266 / 220317534).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 172.0, Dec = -11.3 (J2000 degrees, equivalent to J2000 11h 28m, -11d 18'), with a statistical uncertainty of 13.3 degrees.

The angle from the Fermi LAT boresight is 48.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220317534/quicklook/glg_skymap_all_bn220317534.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220317534/quicklook/glg_healpix_all_bn220317534.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220317534/quicklook/glg_lc_medres34_bn220317534.gif


GRB_name: GRB220310A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31765
SUBJECT: GRB 220310A: MITSuME Akeno optical observation
DATE:    22/03/18 00:15:23 GMT
FROM:    Ryohei Hosokawa at Tokyo Institute of Technology  <hosokawa@hp.phys.titech.ac.jp>

R. Hosokawa, Y. Imai, K. L. Murata, M. Niwano, N. Ito, Y. Takamatsu,
R. Noto, S. Sato, M. Takaku, R. Yamaguchi, Y. Yatsu, and N. Kawai
(Tokyo Tech) report on behalf of the MITSuME collaboration:

We observed the field of GRB 220310A (H. Negoro et al. GCN Circular
#31725, A. Yoshida et al. GCN Circular #31730, P. A. Evans et al. GCN
Circular #31731, V. Lipunov et al. GCN Circular #31732, H. Kumar et
al. GCN Circular #31738, D. Svinkin et al. GCN Circular #31748, Ahmed
M. Fouad et al. GCN Circular #31750, S. Belkin et al. GCN Circular
#31751, A.S. Kozyrev et al. GCN Circular #31756) with the optical
three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm
telescope Akeno. The observation with a series of 60 sec exposures
started at 2022-03-10 15:13:33 UT (14.7 hours after MAXI trigger). We
stacked the images with good conditions. We marginally detected the
optical counterpart candidate at the position reported previously (V.
Lipunov et al. GCN Circular #31732, H. Kumar et al. GCN Circular
#31738, Ahmed M. Fouad et al. GCN Circular #31750).
The magnitudes of the source are as follows.

T0+[hour] | Band | MID-UT | T-EXP[sec] | candidate magnitude
------------------------------------------------------------
16.1 | g' |2022-03-10 16:32:13 | 6720.0 | 19.62+/-0.18
16.1 | Rc |2022-03-10 16:32:13 | 6780.0 | 19.67+/-0.18
16.1 | Ic |2022-03-10 16:32:13 | 6780.0 | 19.05+/-0.23
------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time

We used PS1 catalog for flux calibration.
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: GRB220317A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31766
SUBJECT: GRB 220317A: Swift/BAT-GUANO detection outside the coded FOV
DATE:    22/03/18 15:15:50 GMT
FROM:    Aaron Tohuvavohu at U Toronto  <aaron.tohu@gmail.com>

Aaron Tohuvavohu (U Toronto), James DeLaunay (UAlabama), Gayathri
Raman (PSU), Jamie A. Kennea (PSU), report:

Swift/BAT did not localize GRB 220317A onboard (T0:
2022-03-17T12:48:30 UTC, Fermi/GBM GCN 31763).

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,
arXiv:2111.01769), detects the burst with a sqrt(TS) of 10.2 in a
8.192 s analysis time bin.

NITRATES results are consistent with a burst coming from outside the
coded FoV, as indicated by the Fermi/GBM localization (GCN 31763).

See Section 9.1 and Figure 20 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: GRB220319A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31769
SUBJECT: GRB 220319A: Swift detection of a burst
DATE:    22/03/19 18:07:27 GMT
FROM:    Kim Page at U.of Leicester  <kimlpage1978@gmail.com>

K. L. Page (U Leicester), S. D. Barthelmy (GSFC), J.D. Gropp (PSU),
J. A. Kennea (PSU), A. Y. Lien (U Tampa), D. M. Palmer (LANL) and
T. M. Parsotan (GSFC/UMBC/CRESSTII) report on behalf of the Neil
Gehrels Swift Observatory Team:

At 17:40:33 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 220319A (trigger=1098132).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 218.207, +61.289 which is 
   RA(J2000) = 14h 32m 50s
   Dec(J2000) = +61d 17' 20"
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 10 sec.  The peak count rate
was ~1400 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 17:42:14.5 UT, 101.2 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 218.22471, 61.29389 which is equivalent
to:
   RA(J2000)  = 14h 32m 53.93s
   Dec(J2000) = +61d 17' 38.0"
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This
location is 35 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 250 seconds with the U filter starting
317 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 100% of the
XRT error circle. The typical 3-sigma upper limit has been about 19.2 mag. The
8'x8' region for the list of sources generated on-board covers 100% of the XRT
error circle. The list of sources is typically complete to about 18.0 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.010. 

Burst Advocate for this burst is K. L. Page (kimlpage1978 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: GRB220319A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31770
SUBJECT: GRB 220319A: MASTER Global Robotic Net optical observations 
DATE:    22/03/19 18:09:16 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V.Lipunov, A.Kuznetsov, O.Gress,E.Gorbovskoy, N.Tyurina, P.Balanutsa, K.Zhirkov,
A.Chasovnikov, D.Vlasenko, G.Antipov, V.Senik, D.Kuvshinov, V.Topolev,
Ya.Kechin, Yu.Tselik (Lomonosov Moscow State University, SAI, Physics Department),
C.Francile, R. Podesta, C.Lopez, F. Podesta (Observatorio Astronomico Felix Aguilar OAFA),
D.A.H.Buckley (SAAO),
R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.Corella,
L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory),
N.M.Budnev (ISU,API),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov (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) was pointed to the SWIFT BAT GRB 220319A (GRB220319.74, trigger No 1098132,
14h 32m 49.68s , +61d 17m 20.4s, R=0.05 Page et al. GCN 31769 
https://gcn.gsfc.nasa.gov/other/1098132.swift )
errorbox  38 sec after notice time (62 sec after trigger time) at 
2022-03-19 17:41:35 UT, with upper limit up to  15.6 mag .
The observations began at zenith distance = 57 deg. The sun  altitude  is -19.9 deg.

The galactic latitude b = 52 deg., longitude l = 103 deg.


Real time updated cover map and OT, that can be discovered,will be available here:
https://master.sai.msu.ru/site/master2/observ.php?id=1915275

We obtain a following upper limits.

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

       67 |      MASTER-Tavrida |  P\ |    10 | 14.9 |
      102 |      MASTER-Tavrida |  P\ |    20 | 15.6 |
      142 |      MASTER-Tavrida |  P\ |    20 | 15.4 |


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


GRB_name: GRB220319A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31771
SUBJECT: GRB 220319A: Enhanced Swift-XRT position
DATE:    22/03/20 07:19:20 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 1697 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 220319A, 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 = 218.22421, +61.29496 which is equivalent
to:

RA (J2000): 14h 32m 53.81s
Dec (J2000): +61d 17' 41.9"

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: GRB220319A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31772
SUBJECT: GRB 220319A: Swift-XRT refined Analysis
DATE:    22/03/20 07:30:51 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

J. D. Gropp (PSU), J.P. Osborne (U. Leicester), A.P. Beardmore (U.
Leicester), P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), E.
Ambrosi  (INAF-IASFPA) , J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto)
and K.L. Page report on behalf of the Swift-XRT team:

We have analysed 6.4 ks of XRT data for GRB 220319A (Page et al. GCN
Circ. 31769), from 108 s to 36.4 ks after the  BAT trigger. The data
are entirely in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Goad et al. (GCN Circ. 31771).

The light curve can be modelled with a power-law decay with a decay
index of alpha=0.86 (+0.08, -0.07).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.2 (+0.5, -0.4). The
best-fitting absorption column is  2.2 (+1.5, -1.2) x 10^21 cm^-2, in
excess of the Galactic value of 1.5 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 3.2 x 10^-11 (4.9 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      2.2 (+1.5, -1.2) x 10^21 cm^-2
Galactic foreground: 1.5 x 10^20 cm^-2
Excess significance: 2.8 sigma
Photon index:      2.2 (+0.5, -0.4)

If the light curve continues to decay with a power-law decay index of
0.86, the count rate at T+24 hours will be 2.1 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 6.6 x
10^-14 (1.0 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01098132.

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


GRB_name: GRB220319A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31773
SUBJECT: GRB 220319A: Mondy optical uper limit
DATE:    22/03/20 09:57:51 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed the field of GRB 220319A (Page et al., GCN 31769) with 
AZT-33 telescope of Mondy observatory starting on Mar. 19 (UT) 18:25:41. 
We do not detect any optical counterpart within the Swift/XRT error box 
(Page et al., GCN 31769; Goad et al., GCN 31771). Preliminary photometry 
of the field  is following

Date       UT start t-T0    Filter     Exp.   OT   Err  UL(3sigma)

2022-03-19 18:25:41 0.04523  R         40*60  n/d  n/d  21.7

The photometry is based on the nearby SDSS-DR12 stars R (Lupton
transformations)
R.A. Dec R
14:33:05.13264 +61:18:55.9584 16.1498
14:32:35.99328 +61:17:16.0764 16.5417


GRB_name: GRB220319A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31774
SUBJECT: GRB 220319A: LCO Optical Upper Limit
DATE:    22/03/20 10:22:27 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 220319A (Page et al., GCN 31769) with the LCO 1-m Sinistro instrument at the Teide Observatory, Tenerife site, on March 19, from 23:48 to March 20, 00:15 UT (corresponding to 5.68 to 6.13 hours from the GRB trigger time) with the Bessel R and I filters.

We performed a series of 3x300s exposures in I and R bands. We do not detect an optical counterpart within the XRT enhanced error region (Goad et al., GCN 31771) in either band, consistent with the non-detection from Mondy (Belkin et. al, GCN 31773). The following upper limits are calculated using the USNO-B.1 catalog as reference:

R>21.44
I>20.47

These magnitudes are not corrected for galactic extinction.

R.S. is funded by NSF AST grant #1831682


GRB_name: GRB220319A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31775
SUBJECT: GRB220319A: Optical observations from NOT
DATE:    22/03/20 13:47:37 GMT
FROM:    Antonio de Ugarte Postigo at OCA  <deugarte@oca.eu>

A. de Ugarte Postigo (OCA) and R. Clavero Jimenez (NOT) 
report on behalf of a larger collaboration:

We observed the field of GRB220319A (Page et al. GCN31769) 
with the 2.5m Nordic Optical Telescope equipped with AlFOSC. 
Observations consisted of 3x300s in r and 5x200s in z. Due to variable 
weather conditions, the observation was attempted twice, between 
22:12 and 22:47 UT and between 00:10-00:48 UT (starting 4.53 and 
6.49 hr after the burst). We also note the high background due to the 
illumination from the almost full Moon. The first attempt had a seeing 
of 1.5â€œ in r and 1.3â€œ in z and was affected by some dome vignetting 
due to the low elevation. The second observation had better conditions 
with 1.2â€œ seeing in r and 1.1â€œ in z. 

In a preliminary reduction, we do not detect any new source within or 
near the refined XRT position (Goad et al. GCN 31771) in any of the 
images. We estimate a 3-sigma limit of z > 21.5 mag in the first epoch 
and > 22.5 mag in the second epoch.


GRB_name: GRB220319A
Detection_method: MITSuME
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31776
SUBJECT: GRB 220319A: MITSuME Akeno optical upper limits
DATE:    22/03/20 16:06:24 GMT
FROM:    Ryohei Hosokawa at Tokyo Institute of Technology  <hosokawa@hp.phys.titech.ac.jp>

R. Hosokawa, Y. Imai, K. L. Murata, M. Niwano, N. Ito, Y. Takamatsu,
R. Noto, S. Sato, M. Takaku, R. Yamaguchi, Y. Yatsu, and N. Kawai
(Tokyo Tech) report on behalf of the MITSuME collaboration:

We observed the field of GRB 220319A (K. L. Page et al. GCN Circular
#31769, V.Lipunov et al. GCN Circular #31770, M.R. Goad et al. GCN
Circular #31771, J. D. Gropp et al. GCN Circular #31772, S. Belkin et
al. GCN Circular #31773, R. Strausbaugh et al. GCN Circular #31774, A.
de Ugarte Postigo et al. GCN Circular #31775) with the optical three
color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm
telescope Akeno. The observation with a series of 10 sec exposures
started at 2022-03-19 17:41:30 UT (56.7 seconds after Swift BAT
trigger). We stacked the images with good conditions. We did not
detect any sources within the XRT error region (M.R. Goad et al. GCN
Circular #31771). We obtained the 5-sigma limits of the stacked images
as follows.

T0+[sec] | MID-UT | T-EXP[sec] | 5-sigma limits
-------------------------------------------------------------
101  | 2022-03-19 17:42:14 | 50   | g'>17.0, Rc>16.8, Ic>16.5
762  | 2022-03-19 17:53:16 | 560  | g'>18.5, Rc>18.3, Ic>17.9
4925 | 2022-03-19 19:02:38 | 5520 | g'>19.8, Rc>19.9, Ic>19.6
-------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time

We used PS1 catalog for flux calibration.
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: GRB220321A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31777
SUBJECT: GRB 220321A: Fermi GBM Final Localization
DATE:    22/03/21 15:44:33 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

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

At 06:46:22.00 UT on 21 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220321A (trigger 669537987 / 220321282).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 170.8, Dec = 28.9 (J2000 degrees, equivalent to J2000 11h 23m, +28d 54'), with a statistical uncertainty of 8.6 degrees.

The angle from the Fermi LAT boresight is 57.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220321282/quicklook/glg_skymap_all_bn220321282.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220321282/quicklook/glg_healpix_all_bn220321282.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220321282/quicklook/glg_lc_medres34_bn220321282.gif


GRB_name: GRB220317A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31778
SUBJECT: GRB 220317A: Fermi GBM detection
DATE:    22/03/21 16:46:18 GMT
FROM:    Rachel Hamburg at UAH  <rkh0007@uah.edu>

R. Hamburg (UAH) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 12:48:30.66 UT on 17 March 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 220317A (trigger 669214115 / 220317534).
which was also detected by the Swift/BAT-GUANO (Tohuvavohu et al. 2022, GCN
31766).

The angle from the Fermi LAT boresight at the GBM trigger time is 48
degrees.

The GBM light curve shows two peaks with a duration (T90)
of about 14 s (50-300 keV). The time-averaged spectrum
from T0-6.1 s to T0+8.2 s is best fit by a power law
function with an exponential high-energy cutoff.
The power law index is -1.1 +/- 0.2 and the cutoff
energy, parameterized as Epeak, is 248 +/- 96 keV.

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+4.4 s in the 10-1000 keV band
is 1.6 +/- 0.2 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: GRB220320A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31779
SUBJECT: GRB 220320A: AstroSat CZTI detection
DATE:    22/03/22 07:36:52 GMT
FROM:    Gaurav Waratkar at IIT,Bombay  <gauravwaratkar@iitb.ac.in>

R. Gopalakrishnan (IUCAA), V. Prasad (IUCAA), A. Suresh (IITB), G.
Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya
(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 ML pipeline (Abraham et al.,
2021, MNRAS, 504, 3084) and the CIFT framework (Sharma et al., 2021,
JApA, 42, 73) showed detection of a bright long GRB 220320A which was
also detected by IPN (contributed by Konus-Wind at GCN Notices), and
Fermi - GBM (Trigger - 669443999).

The source was clearly detected in the 20-200 keV energy range. The
light curve peaks at 2022-03-20 04:39:59.25 UT. The measured peak count
rate associated with the burst is 2398 (+336, -71) counts/s above the
background in the combined data of four quadrants, with a total of 5427
(+307, -331) counts. The local mean background count rate was 507 (+5,
-9) counts/s. Using cumulative rates, we measure a T90 of 11 (+1, -1) s.

It was also clearly detected in the CsI anticoincidence (Veto) detector
in the 100-500 keV energy range. The light curve showed a peak at
2022-03-20 04:39:59.13 UT. The measured peak count rate is 3438 (+112,
-122) counts/s  above the background in the combined Veto data of four
quadrants, with a total of 10543 (+502, -570) counts. The local mean
background count rate was 1529 (+5, -5) counts/s. We measure a T90 of 16
(+3, -3) s from the cumulative Veto light curve.

CZTI GRB detections are reported regularly on the payload site at
http://astrosat.iucaa.in/czti/?q=grb [1]. CZTI is built by a TIFR-led
consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC,
and PRL. The Indian Space Research Organisation funded, managed, and
facilitated the project. 

Links:
------
[1] http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB220316A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31780
SUBJECT: GRB 220316A: AstroSat CZTI detection
DATE:    22/03/22 13:32:56 GMT
FROM:    Gaurav Waratkar at IIT,Bombay  <gauravwaratkar@iitb.ac.in>

R. Gopalakrishnan (IUCAA), V. Prasad (IUCAA), G. Waratkar (IITB), A.
Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (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 detection of a long GRB 220316A which was
also detected by Fermi - GBM (TrigNum - 669122742), and Konus - Wind
(GCN Notices).

The source was clearly detected in the 20-200 keV energy range. The
light curve showed multiple peaks of emission with the strongest peak at
2022-03-16 11:25:40.5 UT. The measured peak count rate associated with
the burst is 266 (+48, -18) counts/s above the background in the
combined data of three quadrants, with a total of 2313 (+321, -294)
counts. The local mean background count rate was 361 (+2, -3) counts/s.
Using cumulative rates, we measure a T90 of 30 (+6, -4) s.

It 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 2022-03-16 11:25:39.22 UT. The
measured peak count rate is 887 (+76, -73) counts/s  above the
background in the combined Veto data of four quadrants, with a total of
4547 (+524, -584) counts. The local mean background count rate was 1454
(+4, -4) counts/s. We measure a T90 of 25 (+5, -2) s from the cumulative
Veto light curve.

CZTI GRB detections are reported regularly on the payload site at
http://astrosat.iucaa.in/czti/?q=grb [1]. CZTI is built by a TIFR-led
consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC,
and PRL. The Indian Space Research Organisation funded, managed, and
facilitated the project.

 

Links:
------
[1] http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB220319A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31781
SUBJECT: GRB 220319A: Swift-BAT refined analysis
DATE:    22/03/22 15:40:46 GMT
FROM:    Sibasish Laha at GSFC  <sibasish.laha@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-239 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 220319A (trigger #1098132)
(Page et al., GCN Circ. 31769).  The BAT ground-calculated position is
RA, Dec = 218.139, 61.291 deg which is
   RA(J2000)  =  14h 32m 33.4s
   Dec(J2000) = +61d 17' 26.6"
with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 43%.

The BAT light curve showed a single-peaked
structure with a duration of about 10 sec.
T90 (15-350 keV) is 6.44 +- 1.54 sec (estimated error including systematics).

The time-averaged spectrum from T-0.36 to T+6.56 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
2.15 +- 0.28.  The fluence in the 15-150 keV band is 2.3 +- 0.4 x 10^-07 erg/cm2.
The 1-sec peak photon flux measured from T-0.24 sec in the 15-150 keV band
is 1.5 +- 0.2 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/1098132/BA/


GRB_name: GRB220323A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31782
SUBJECT: GRB 220323A: Fermi GBM Final Real-time Localization
DATE:    22/03/23 12:20:36 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 12:10:11 UT on 23 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220323A (trigger 669730216.566582 / 220323507).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 355.2, Dec = 71.9 (J2000 degrees, equivalent to J2000 23h 40m, 71d 54'), with a statistical uncertainty of 9.9 degrees.

The angle from the Fermi LAT boresight is 25.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220323507/quicklook/glg_skymap_all_bn220323507.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220323507/quicklook/glg_healpix_all_bn220323507.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220323507/quicklook/glg_lc_medres34_bn220323507.gif


GRB_name: GRB220320A
Detection_method: IPN Triangulation
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31783
SUBJECT: IPN triangulation of GRB 220320A
DATE:    22/03/23 12:27:20 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, and C. Wilson-Hodge
on behalf of the Fermi GBM team,

E. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB 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 bright, long-duration GRB 220320A
(AstroSat-CZTI detection: Gopalakrishnan et al., GCN Circ. 31779)
was detected by Fermi (GBM trigger 669443999), Konus-Wind,
INTEGRAL (SPI-ACS), Mars-Odyssey (HEND), BepiColombo (MGNS),
CALET (CGBM), and AstroSat (CZTI) at about 16794 s UT (04:39:54).

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
    94.150 (06h 16m 36s) -55.909 (-55d 54' 31")
  Corners:
    94.226 (06h 16m 54s) -55.949 (-55d 56' 58")
    94.048 (06h 16m 12s) -55.915 (-55d 54' 54")
    94.074 (06h 16m 18s) -55.868 (-55d 52' 04")
    94.252 (06h 17m 00s) -55.902 (-55d 54' 08")
  ---------------------------------------------
The error box area is 19 sq. arcmin, and its maximum
dimension is 7 arcmin (the minimum one is 3 arcmin).
The Sun distance was 92 deg.

This box may be improved.

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

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB220320_T16796/IPN

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


GRB_name: GRB220323A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31784
SUBJECT: GRB 220323A: AGILE/MCAL detection
DATE:    22/03/23 15:14:50 GMT
FROM:    Alessandro Ursi at INAF/IAPS  <alessandro.ursi@gmail.com>

A. Ursi (INAF/IAPS), M. Romani (INAF/OA-Brera), C. Pittori, F. Verrecchia
(SSDC, and INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), A.
Argan, M. Cardillo, C. Casentini, Y. Evangelista, L. Foffano, E. Menegoni,
G. Piano (INAF/IAPS), F. Lucarelli (SSDC, and INAF/OAR), A. Bulgarelli, A.
Di Piano, V. Fioretti, F. Fuschino, N. Parmiggiani (INAF/OAS-Bologna), M.
Marisaldi (INAF/OAS-Bologna, and Bergen University), M. Pilia, A. Trois
(INAF/OA-Cagliari), I. Donnarumma (ASI), A. Giuliani (INAF/IASF-Mi), F.
Longo (Univ. Trieste and INFN Trieste), and P. Tempesta (TeleSpazio),
report on behalf of the AGILE Team:

The AGILE MiniCALorimeter (MCAL; 0.4-100 MeV) detected the short GRB
220323A at T0 = 2022-03-23 12:10:11 (UTC), reported by Fermi GBM (GCN
#31782).

The event lasted 0.35 s and released 295 counts in the detector, above a
background rate of 630 Hz. The time-integrated spectrum of the burst can be
fitted in the energy range 0.4-2 MeV with a power-law with ph.ind = 2.44
(-0.70/+1.13), resulting in a reduced chi-squared of 1.06 (21 d.o.f.) and a
fluence of 5.6e-07 erg/cm^2 (90% confidence level), in the same energy
range. The MCAL light curve can be found at
http://www.agilescienceapp.it/notices/077531_GRB_575122215.552228.png . At
the T0, the event was 134 deg off-axis.

The burst is also clearly visible in the AGILE scientific ratemeters of the
MCAL detector, where it released a total number of 1550 counts (above a
background rate of 1230 Hz). The AGILE MCAL ratemeters light curve can be
found at http://www.agilescienceapp.it/notices/GRB220323A_AGILE_RM.png .

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. Please
note that in the MCAL notice #575122215 the T0 was affected by a temporal
shift of about +4.0 sec due to episodic automated ground software problems
which are then corrected offline.


GRB_name: GRB220319A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31785
SUBJECT: GRB 220319A: GRANDMA observations
DATE:    22/03/24 14:29:52 GMT
FROM:    Marie Anne Bizouard at ARTEMIS/CNRS  <marieanne.bizouard@oca.eu>

M. Bizouard (OCA/Artemis), P-A. Duverne (IJCLAB), A. Iskandar (XAO),
D. Datashvili (AbAO), M. Blazek (FZU), D. Turpin (CEA), T. Midavaine (KNC)
S. Antier (OCA/Artemis), I. Tosta eMelo (INFN-LNS), X. F. Wang (TSU/BJP),
J. Zhu (BJP), X. Song (BJP), S. Karpov (FZU), A. Kann (IAA-CSIC),
D. Marchais (KNC), A. Popowicz (KNC), A. Oksanen (KNC), M. Serrau (KNC),
M. Freeberg (KNC),  A. Klotz (IRAP-OMP), R. Kneip (KNC), E. Broens (KNC),
O. Aguerre (KNC), report  on behalf of the GRANDMA collaboration:


The GRANDMA telescope network responded to the alert of GRB 220319A 
(Page et al.
GCN 31769). The first observations started 14 min after the BAT trigger 
time.
No new object was detected within the XRT enhanced error region (Goad et 
al. GCN
31771). The observations were affected by the nearby full Moon and in 
some cases
also by Sahara dust.

In the following table we report the preliminary photometry of our 
observations.
Upper limits are reported at the 3-sigma limit, in the AB system.

T-T0 (hr)| MJD    | Observatory| Filter| Upp.Mag.
____________________________________________________
0.23 |59657.746539| KNC-HAN    |  Lum      | 18.6
0.94 |59657.775880| KNC-HAN    |  Lum      | 18.7
1.38 |59657.794039| KNC-TJML   |  Clear    | 15.7
2.79 |59657.852604| KNC-T-BRO  |  Clear    | 18.6
2.89 |59657.856921| KNC-K26    |  Lumen    | 18.2
4.01 |59657.903715| KNC-T-CAT  |  Blue     | 19.4
4.01 |59657.903715| KNC-T-CAT  |  Green    | 19.5
4.01 |59657.903715| KNC-T-CAT  |  Red      | 18.2
5.47 |59657.964502| KNC-TJMS-PS|  Lumen    | 20.0
5.62 |59657.970540| ALi-50     |  Clear    | 20.1
7.22 |59658.037350| KNC-T-AGU  |  Lum      | 18.8
10.85|59658.188623| C11FREE    |  Rc       | 18.7

Most of these observations were performed in the context of the 
Kilonova-Catcher
programme (KNC), a professional-amateur collaboration within the GRANDMA
project, and in some cases using non-standard filters. The KNC 
images have been
processed using the MUPHOTEN pipeline (Duverne et al. 2021) and 
photometry was
performed using field stars from the PanSTARRS catalogue as reference.

GRANDMA is a worldwide coordinated 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: GRB220323A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31786
SUBJECT: GRB 220323A: AstroSat CZTI detection
DATE:    22/03/25 06:39:21 GMT
FROM:    Gaurav Waratkar at IIT,Bombay  <gauravwaratkar@iitb.ac.in>

R. Gopalakrishnan (IUCAA), V. Prasad (IUCAA), G. Waratkar (IITB), A.
Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (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 detection of a short GRB 220323A which was
also detected by Fermi - GBM (GCN 31782) and AGILE/MCAL (Ursi et al.,
GCN 31784). 

The source was clearly detected in the 20-200 keV energy range. The
light curve peaks at 2022-03-23 12:10:10.55 UT. The measured peak count
rate associated with the burst is 1120 (+888, -4) counts/s above the
background in the combined data of three quadrants, with a total of 141
(+48, -50) counts. The local mean background count rate was 386 (+13,
-34) counts/s. Using cumulative rates, we measure a T90 of 0.32 (+0.22,
-0.15) s. 

It was also detected in the CsI anticoincidence (Veto) detector in the
100-500 keV energy range. 

CZTI GRB detections are reported regularly on the payload site at
http://astrosat.iucaa.in/czti/?q=grb [1]. CZTI is built by a TIFR-led
consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC,
and PRL. The Indian Space Research Organisation funded, managed, and
facilitated the project. 

Links:
------
[1] http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB220325A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31787
SUBJECT: GRB 220325A: Swift detection of a burst
DATE:    22/03/25 17:27:31 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

M. Ferro (INAF-OAB), M. G. Bernardini (INAF-OAB),
R. Brivio (INAF-OAB), P. D'Avanzo (INAF-OAB), J.D. Gropp (PSU),
J. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL), S. Laha (GSFC/UMBC),
F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester),
D. M. Palmer (LANL), T. M. Parsotan (GSFC/UMBC/CRESSTII),
T. Sbarrato (INAF-OAB), B. Sbarufatti (PSU) and M. H. Siegel (PSU)
report on behalf of the Neil Gehrels Swift Observatory Team:

At 17:16:23 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 220325A (trigger=1099310).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 269.485, -7.031 which is 
   RA(J2000) = 17h 57m 56s
   Dec(J2000) = -07d 01' 50"
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 ~8 sec.  The peak count rate
was ~2000 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 17:18:13.2 UT, 110.2 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source located at RA, Dec 269.48760, -7.03776 which
is equivalent to:
   RA(J2000)  = 17h 57m 57.02s
   Dec(J2000) = -07d 02' 15.9"
with an uncertainty of 3.9 arcseconds (radius, 90% containment). This
location is 26 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. 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 114 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 100% of
the XRT 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
XRT 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
0.915. 

Burst Advocate for this burst is M. Ferro (matteo.ferro 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: GRB220324A
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31788
SUBJECT: GRB 220324A: AstroSat CZTI detection
DATE:    22/03/25 17:47:32 GMT
FROM:    Gaurav Waratkar at IIT,Bombay  <gauravwaratkar@iitb.ac.in>

R. Gopalakrishnan (IUCAA), V. Prasad (IUCAA), G. Waratkar (IITB), A.
Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (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 detection of a long GRB 220324A which was
also detected by Fermi - GBM (Trigger Number - 669782349).

The source was clearly detected in the 20-200 keV energy range. The
light curve peaks at 2022-03-24 02:39:09.50 UT. The measured peak count
rate associated with the burst is 200 (+44, -28) counts/s above the
background in the combined data of all four quadrants, with a total of
2304 (+346, -331) counts. The local mean background count rate was 502
(+2, -2) counts/s. Using cumulative rates, we measure a T90 of 22 (+5,
-4) s.

It was also clearly detected in the CsI anticoincidence (Veto) detector
in the 100-500 keV energy range. The light curve showed a single peak of
emission at 2022-03-24 02:38:00.95 UT. The measured peak count rate is
169 (+83, -10) counts/s  above the background in the combined Veto data
of four quadrants, with a total of 1428 (+566, -627) counts. The local
mean background count rate was 1687 (+5, -6) counts/s. We measure a T90
of 18 (+5, -9) s from the cumulative Veto light curve.

CZTI GRB detections are reported regularly on the payload site at
http://astrosat.iucaa.in/czti/?q=grb [1]. CZTI is built by a TIFR-led
consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC,
and PRL. The Indian Space Research Organisation funded, managed, and
facilitated the project. 

Links:
------
[1] http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB220325A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31789
SUBJECT: GRB 220325A: MASTER Global Robotic Net optical observations 
DATE:    22/03/25 20:18:18 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V.Lipunov, D.Vlasenko, A.Kuznetsov, O.Gress, E.Gorbovskoy, N.Tyurina, P.Balanutsa, K.Zhirkov, A.Chasovnikov,
G.Antipov, V.Senik, D.Kuvshinov, V.Topolev,Ya.Kechin, Yu.Tselik (Lomonosov Moscow State University, SAI, Physics Department),
C.Francile, R. Podesta, C.Lopez, F. Podesta (Observatorio Astronomico Felix Aguilar OAFA),
D.A.H.Buckley (SAAO),
R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.Corella,
L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory),
N.M.Budnev (ISU,API),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov (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)
was pointed to the SWIFT GRB 220325A ( M. Ferro et al., GCN 31787) errorbox
3287 sec after notice time (3306 sec after trigger time)
at 2022-03-25 18:11:29 UT between rain with snow with upper limit up to 15.1 mag.
  The observations started at zenith distance = 69 deg. The sun  altitude  was -28.4 deg.

The galactic latitude b =  8 deg., longitude l = 21 deg.

Real time updated cover map is available:
https://master.sai.msu.ru/site/master2/observ.php?id=1921440

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


GRB_name: GRB220325A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31790
SUBJECT: GRB 220325A: Enhanced Swift-XRT position
DATE:    22/03/25 20:47:24 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 1551 s of XRT Photon Counting mode data and 3 UVOT
images for GRB 220325A, 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 = 269.48753, -7.03592 which is equivalent
to:

RA (J2000): 17h 57m 57.01s
Dec (J2000): -07d 02' 09.3"

with an uncertainty of 2.4 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: GRB220325A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31791
SUBJECT: Fermi GBM Sub-Threshold Detection of GRB 220325A
DATE:    22/03/26 03:41:37 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

J. Wood (NASA/MSFC) reports on behalf of the Fermi-GBM Team:

There was no Fermi-GBM onboard trigger around the time of GRB 220325A,
which was detected by Swift-BAT at 17:16:23 UT on 25 March, 2022 (Ferro
et al. GCN 31787).

An automated, blind search for short gamma-ray bursts below the onboard
triggering threshold in Fermi-GBM identified GRB 220325A with medium
reliability [1], with a localization consistent with the Swift-BAT
location at the ~2 sigma level, and a discovery timescale of 2.751 s.
The start time of the GBM sub-threshold detection coincides with the time
of the peak photon flux observed by Swift-BAT.

The GBM targeted search [2], the most sensitive, coherent search for
GRB-like signals also identified a transient most significantly on the 2.048 s
timescale, with a location consistent with the Swift-BAT event at
the ~2 sigma level and a signal-to-noise ratio of 12.3,
using the standard search protocol.
The GBM targeted search event was found with the highest
significance with a "soft" spectrum (Band function with
Epeak = 70 keV, alpha = -1.9, beta = -3.7) for a GRB.

This analysis is preliminary.

[1] https://gcn.gsfc.nasa.gov/notices_gbm_sub/669921389.fermi
[2] Goldstein et al. 2019 arXiv:1903.12597


GRB_name: GRB220325B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31792
SUBJECT: GRB 220325B: Fermi GBM Final Localization
DATE:    22/03/26 04:17:29 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

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

At 21:06:13.46 UT on 25 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220325B (trigger 669935178 / 220325879).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 267.2, Dec = +21.5 (J2000 degrees, equivalent to J2000 17h 49m, +21d 30'), with a statistical uncertainty of 11.4 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/2022/bn220325879/quicklook/glg_skymap_all_bn220325879.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220325879/quicklook/glg_healpix_all_bn220325879.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220325879/quicklook/glg_lc_medres34_bn220325879.gif


GRB_name: GRB220325A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31793
SUBJECT: GRB 220325A: 1.3m DFOT Optical upper limit
DATE:    22/03/26 09:35:16 GMT
FROM:    Rahul Gupta at ARIES, India  <rahulbhu.c157@gmail.com>

Rahul Gupta, Amit Ror, Amit Kumar, Dimple, Ankur Ghosh, Amar Aryan, Krishan
Chand, S. B. Pandey, and Kuntal Misra (ARIES) report:


We observed the Swift-BAT and Fermi-GBM Sub-Threshold detected GRB 220325A (
Ferro et al., GCN 31787; Wood, GCN 31791) with 1.3m Devasthal Fast
Optical Telescope
(DFOT) located at Devasthal observatory of Aryabhatta Research Institute of
Observational Sciences (ARIES), India. The observations were started on
2022-03-25 at ~ 22:15 UT, i.e., ~ 5 hours after the BAT trigger. We have
taken multiple frames having an exposure time of 300 sec in the R filter.
We stacked the images after the alignment. We did not detect any new
optical source
within the Swift XRT uncertainty circle (Osborne et al., GCN 31790) in our
stacked image.

We obtain the following 3-sigma upper limit in the stacked image.

Date Start_UT T_start-T0 (hour) Filter  Exp time (sec)  Limiting magnitude
====================================================
2022-03-25 22:15   ~5                 R        300*20            > 21.7


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: GRB220325A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31794
SUBJECT: GRB 220325A: Swift-XRT refined Analysis
DATE:    22/03/26 10:49:46 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), P.A. Evans (U.
Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi  (INAF-IASFPA) , M.
Capalbi (INAF-IASFPA), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto),
B. Sbarufatti (PSU) and M. Ferro report on behalf of the Swift-XRT
team:

We have analysed 6.7 ks of XRT data for GRB 220325A (Ferro et al. GCN
Circ. 31787), from 95 s to 35.5 ks after the  BAT trigger. The data
comprise 8 s in Windowed Timing (WT) mode (taken while Swift was
slewing), with the remainder in Photon Counting (PC) mode. The enhanced
XRT position for this burst was given by Osborne et al. (GCN Circ.
31790).

The light curve can be modelled with a power-law decay with a decay
index of alpha=0.67 (+/-0.06).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.51 (+0.28, -0.16). The
best-fitting absorption column is  3.96 (+1.97, -0.09) x 10^21 cm^-2,
consistent with the Galactic value of 3.9 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 5.2 x 10^-11 (6.5 x
10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      3.96 (+1.97, -0.09) x 10^21 cm^-2
Galactic foreground: 3.9 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:      1.51 (+0.28, -0.16)

If the light curve continues to decay with a power-law decay index of
0.67, the count rate at T+24 hours will be 7.6 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 4.0 x
10^-13 (5.0 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01099310.

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


GRB_name: GRB220325A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31795
SUBJECT: GRB 220325A: LCO Optical Upper Limits
DATE:    22/03/26 13:24:25 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 220325A (Ferro et al., GCN 31787) with the LCO 1-m Sinistro instrument at the McDonald Observatory, Texas, USA site, on March 26, from 09:25 to 09:53 UT (corresponding to 16.15 to 16.62 hours from the GRB trigger time) with the Bessel R and I filters.

We performed a series of 3x300s exposures in I and R bands. We do not detect an optical counterpart within the XRT enhanced error region (Osborne et al., GCN 31790) in either band, consistent with other non-detections (Lipunov et al., GCN 31773; Gupta et al., GCN 31793). The following upper limits are calculated using the USNO-B.1 catalog as reference:

R>21.08
I>20.14

These magnitudes are not corrected for galactic extinction.

R.S. is funded by NSF AST grant #1831682


GRB_name: GRB220326A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31796
SUBJECT: GRB 220326A: Fermi GBM Final Localization
DATE:    22/03/26 15:16:01 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>

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

At 04:09:32.48 UT on 26 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220326A (trigger 669960577 / 220326173).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 185.6, Dec = -31.0 (J2000 degrees, equivalent to J2000 12h 22m, +-31d 00'), with a statistical uncertainty of 11.6 degrees.

The angle from the Fermi LAT boresight is 96.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220326173/quicklook/glg_skymap_all_bn220326173.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220326173/quicklook/glg_healpix_all_bn220326173.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220326173/quicklook/glg_lc_medres34_bn220326173.gif


GRB_name: GRB220325A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31797
SUBJECT: GRB 220325A: Tautenburg observations
DATE:    22/03/26 20:47:50 GMT
FROM:    Ana Nicuesa at TLS Tautenburg  <ana@tls-tautenburg.de>

A. Nicuesa Guelbenzu, S. Klose, B. Stecklum, S. Melnikov, and
U. Laux (all Tautenburg) report:

We observed the field of GRB 220325A (Ferro et al. GCN 31787) with the
Tautenburg 1.34m Schmidt telescope equipped with the TAUKAM 6k x 6k
CCD camera. Observations consisted of 3x3 min exposures using the
Sloan r, i, and z-band filter. The airmass was 2.1, the seeing
relatively poor (3 arcsec).

Inside the enhanced XRT error circle (Osborne et al., GCN 31790) we do not
find any source down to the following magnitudes:

r > 20.7 mag (AB, 3 sigma), mean time: 2022-03-26, 03:05:34 UT,
i > 20.6 mag (AB, 3 sigma), mean time: 2022-03-26, 03:16:22 UT,
z > 19.7 mag (AB, 3 sigma). mean time: 2022-03-26, 03:27:10 UT,

calibrated against the Pan-STARRS catalog.


GRB_name: GRB220325A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31799
SUBJECT: GRB 220325A: Swift-BAT refined analysis
DATE:    22/03/28 15:14:06 GMT
FROM:    Sibasish Laha at GSFC  <sibasish.laha@nasa.gov>

S. Laha (GSFC/UMBC), S. D. Barthelmy (GSFC),
H. A. Krimm (NSF), 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 220325A (trigger #1099310)
(Ferro et al., GCN Circ. 31787).  The BAT ground-calculated position is
RA, Dec = 269.469, -7.055 deg which is
   RA(J2000)  =  17h 57m 52.7s
   Dec(J2000) = -07d 03' 18.4"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 52%.

The BAT light curve showed a complex
structure with a duration of about 6 sec.
T90 (15-350 keV) is 3.50 +- 0.56 sec (estimated error including systematics).

The time-averaged spectrum from T-0.97 to T+3.02 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 0.69 +- 1.13,
and Epeak of 39.3 +- 8.9 keV (chi squared 63.15 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 2.9 +- 0.4 x 10^-07 erg/cm2
and the 1-sec peak flux measured from T+0.53 sec in the 15-150 keV band is
2.0 +- 0.3 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 2.06 +- 0.17 (chi squared 69.80 for 57 d.o.f.).  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/1099310/BA/


GRB_name: GRB211024B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31800
SUBJECT: GRB 211024B: Host galaxy redshift from X-shooter/VLT
DATE:    22/03/28 15:57:26 GMT
FROM:    Antonio de Ugarte Postigo at OCA  <deugarte@oca.eu>

A. de Ugarte Postigo (Artemis/OCA), B. Schneider (CEA Paris-Saclay), 
D. B. Malesani (Radboud Univ. and DAWN/NBI), D. A. Kann (IAA-CSIC) 
report on behalf of the Stargate collaboration:

We observed the location of the ultra-long GRB 211024B (Gropp et al. 
GCN 30980, Zhu et al. GCN 30984) using the X-shooter spectrograph 
mounted on the UT3 of ESOâ€™s Very Large Telescope. The observation 
was performed on 27 March 2022 (153 days after the GRB) and 
consisted of 4x1200 s in the UVB and VIS arms and 8x600 s in the NIR 
arm. We used the JH-slit that blocks part of the K-band and in return 
increases the efficiency of the J and H bands, resulting in a wavelength 
coverage between 3000 to 21000 AA. 

In a preliminary reduction we detect two weak emission lines that we 
identify as [OII]3727 and [OIII] 5008, as well as a marginal detection of 
[OII]4960 at a common redshift of z=1.1137+/-0.0002. The other line of 
the OII doublet, [OII]3729 is affected by a sky line and is consequently 
not detected. H-alpha falls within a telluric absorption and H-beta in a 
spectral region of low sensitivity, both resulting in non detections. Given 
the spatial coincidence of these emissions with the afterglow, we identify 
the underlying object as the host galaxy and propose this as the redshift 
of the GRB.

We acknowledge expert support from the ESO staff in Paranal, in 
particular Cedric Ledoux and Michael Abdul-Masih.


GRB_name: GRB220325A
Detection_method: Swift-UVOT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31801
SUBJECT: GRB 220325A: Swift/UVOT Upper Limits
DATE:    22/03/28 16:02:38 GMT
FROM:    Paul Kuin at MSSL  <npkuin@gmail.com>

N. P. M. Kuin (UCL-MSSL) and M. Ferro (INAF-OAB)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 220325A
114 s after the BAT trigger (Ferro et al., GCN Circ. 31787).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 31790)
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           114          264          147         >20.8
u_FC               326          576          246         >20.1
white              114         5035          488         >21.0
v                  657         1234           78         >18.7
b                  582         4893          255         >20.1
u                  326         4688          481         >20.3
w1                 707          726           19         >17.9

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.915 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB220320A
Detection_method: Konus-Wind Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31802
SUBJECT: Konus-Wind observation of GRB 220320A
DATE:    22/03/28 16:58:44 GMT
FROM:    Anastasia Tsvetkova at Ioffe Institute  <tsvetkova@mail.ioffe.ru>

A. Tsvetkova,  D. Frederiks, D. Svinkin,
M. Ulanov, A. Lysenko, A. Ridnaia and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration, bright GRB 220320A
(AstroSat CZTI detection: Gopalakrishnan et al., GCN 31779;
IPN triangulation: Kozyrev et al., GCN 31783)
triggered Konus-Wind at T0=16796.141 s UT (04:39:56.141).

The burst light curve shows a multi-peaked structure
which starts at ~T0-18.8 s and has a total duration of~52.8 s
The emission is seen up to ~20 MeV.

As observed by Konus-Wind, the burst
had a fluence of 6.05(-0.50,+0.52)x10^-5 erg/cm2,
and a 64-ms peak energy flux, measured from T0+4.048 s,
of 2.50(-0.34,+0.34)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst
(measured from T0 to T0+20.480 s)
is best fit in the 20 keV - 20 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.84(-0.09,+0.10),
the high energy photon index beta = -2.27(-0.15,+0.11),
the peak energy Ep = 224(-21,+24) keV,
chi2 = 100/97 dof.

The spectrum near the peak count rate
(measured from T0 to T0+4.352 s)
is best fit in the 20 keV - 20 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.43(-0.11,+0.12),
the high energy photon index beta = -2.31(-0.17,+0.13),
the peak energy Ep = 311(-29,+33) keV,
chi2 = 67/86 dof.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB220320_T16796/

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.


GRB_name: GRB220320A
Detection_method: CALET
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31803
SUBJECT: GRB 220320A: Detection by VZLUSAT-2
DATE:    22/03/29 04:06:06 GMT
FROM:    Jakub Ripa at Masaryk University  <ripa.jakub@mail.muni.cz>

J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), M. Ohno (Eotvos 
U./Hiroshima U.),  N. Werner  (Masaryk U.),  L. Meszaros (Konkoly 
Observatory), H. Takahashi (Hiroshima U.), B. Csak (Konkoly 
Observatory), M. Topinka, F. Munz, F. Hroch (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 bright, long-duration GRB 220320A (AstroSat-CZTI detection: 
Gopalakrishnan et al., GCN Circ. 31779; localized by IPN: Kozyrev et al. 
GCN Circ. 31783 and detected also by Fermi/GBM trigger 669443999, 
CALET/CGBM trigger 1331786356, Konus-Wind, INTEGRAL/SPI-ACS at about 
04:39:54 UT) was also detected by one of the two GRB detectors on board 
of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).

This is the first time that a GRB was observed by the VZLUSAT-2 3U CubeSat.

The data acquisition was performed by GRB detector unit no. 1 (the unit 
no. 0 was turned off). The detector was performing a several hours long 
background monitoring survey with 15 s temporal resolution, which is not 
optimal for GRB search. Much finer resolution is planned for the nominal 
operation. The 46 sigma detection significance was confirmed at around 
04:39:55 UTC.

The light curve obtained by VZLUSAT-2 is available here:
https://vzlusat2.konkoly.hu/static/share/GRB220320A_GCN_VZLUSAT_2.pdf

GRB detectors on VZLUSAT-2 are a demonstration payload for a future 
CubeSats 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: GRB220325A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31804
SUBJECT: GRB 220325A: GRANDMA observations
DATE:    22/03/29 18:08:27 GMT
FROM:    Sarah Antier at OCA  <sarah.antier@oca.eu>

C. Andrade, M. Coughlin (UNM), K. Noysena (NARIT), W. Kiendrebeogo (UJS),
I. Tosta e Melo (INFN-LNS), X. F. Wang (TSU/BJP), F. Navarete (NOIRLab/SOAR)
J. Zhu (BJP), L. Wang (XAO), A. Iskandar (XAO), X. Zeng (XAO), L. Abe,
Ph. Bendjoya, J.-P. Rivet (Lagrange/OCA), D. Vernet (Galilee/OCA),
S. Antier, A. de Ugarte Postigo (Artemis/OCA), A. M. Fouad, A. Taky,
A. Shokry, I. Elhousiny, A. Eid, M. Farouk (NRIAG), P.A. Duverne (IJCLAB)
report on behalf of the GRANDMA collaboration:

The GRANDMA telescope network responded to the alert of GRB 220325A
(Palmer et al. GCN 31787). The first observations started 4.28 h after
the BAT trigger time.

No new object was detected within the XRT enhanced error region (Evans et
al. GCN 31794). In the following table we report the preliminary photometry
of our observations. Upper limits are reported at the 3-sigma limit, in the
AB system.

T-T0 (hr)| MJD    | Observatory| Exposure| Filter   | Upp.Lim. (AB)
_____________________________________________________________________
04.28 |59663.89971| SNOVA      | 9x300s  | Bessel R | 20.1
04.44 |59663.90475| NOWT       | 11x180s | Bessel R | 19.7
08.11 |59664.05765| KAO        | 22x50s  |  SDSS i  | 21.2
10.14 |59664.14304| C2PU       | 16x240s |  SDSS r  | 20.8

These limits are consistent with the non-detections previously reported
(Gupta et al. GCN 31793, Strausbaugh et al. GCN 31795, Nicuesa Guelbenzu et
al. GCN 31797).

The photometry of NOWT and SNOVA was performed using field stars from the
APASS catalog. The KAO and C2PU image have been processed using field stars
from the PanSTARRS-DR1 catalog and with the MUPHOTEN pipeline (Duverne et
al. 2021).

The magnitudes are not corrected for the Galactic extinction in the
direction of the burst.

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: GRB220330A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31806
SUBJECT: GRB 220330A: Fermi GBM Final Real-time Localization
DATE:    22/03/30 12:38:33 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 12:28:09 UT on 30 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220330A (trigger 670336094.273364 / 220330520).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 324.1, Dec = 63.1 (J2000 degrees, equivalent to J2000 21h 36m, 63d 06'), with a statistical uncertainty of 3.8 degrees.

The angle from the Fermi LAT boresight is 28.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220330520/quicklook/glg_skymap_all_bn220330520.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220330520/quicklook/glg_healpix_all_bn220330520.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220330520/quicklook/glg_lc_medres34_bn220330520.gif


GRB_name: GRB220330A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31807
SUBJECT: Fermi GRB 220330A: Global MASTER-Net observations report 
DATE:    22/03/30 13:30:29 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, D. Vlasenko, 
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(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. Gres, N.M. Budnev
(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),

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


MASTER-OAGH robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) started inspect of the Fermi GRB 220330A ( Fermi GBM team, GCN 31806) errorbox  37 sec after notice time and 66 sec after trigger time at 2022-03-30 12:29:15 UT, with upper limit up to  17.1 mag. Observations started at twilight.  The observations began at zenith distance = 47 deg. The sun  altitude  is -9.6 deg. 

MASTER-Amur robotic telescope  located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB 220330A errorbox  51 sec after notice time and 80 sec after trigger time at 2022-03-30 12:29:29 UT, with upper limit up to  17.9 mag. The observations began at zenith distance = 67 deg. The sun  altitude  is -23.1 deg. 

The galactic latitude b =  8 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=1927341

We obtain a following upper limits.  

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

      71 | 2022-03-30 12:29:15 |         MASTER-OAGH | (21h 20m 30.17s , +62d 49m 52.5s) |   C |    10 | 16.9 |        
      91 | 2022-03-30 12:29:29 |         MASTER-Amur | (21h 30m 59.44s , +63d 07m 26.5s) |   C |    20 | 16.9 |        
     107 | 2022-03-30 12:29:46 |         MASTER-OAGH | (21h 21m 26.31s , +62d 20m 46.1s) |   C |    20 | 17.0 |        
     107 | 2022-03-30 12:29:46 |         MASTER-OAGH | (21h 20m 25.32s , +62d 49m 09.0s) |   C |    20 | 17.1 |        
     130 | 2022-03-30 12:30:09 |         MASTER-Amur | (21h 30m 52.87s , +63d 06m 20.1s) |   C |    20 | 16.9 |        
     148 | 2022-03-30 12:30:27 |         MASTER-OAGH | (21h 20m 25.46s , +62d 50m 10.3s) |   C |    20 | 16.8 |        
     148 | 2022-03-30 12:30:27 |         MASTER-OAGH | (21h 21m 26.38s , +62d 21m 47.1s) |   C |    20 | 16.9 |        
     175 | 2022-03-30 12:30:49 |         MASTER-Amur | (21h 30m 58.51s , +63d 06m 22.2s) |   C |    30 | 17.2 |        
     194 | 2022-03-30 12:31:08 |         MASTER-OAGH | (21h 20m 30.63s , +62d 49m 11.9s) |   C |    30 | 16.8 |        
     194 | 2022-03-30 12:31:08 |         MASTER-OAGH | (21h 21m 31.38s , +62d 20m 48.4s) |   C |    30 | 16.8 |        
     230 | 2022-03-30 12:31:38 |         MASTER-Amur | (21h 30m 55.74s , +63d 08m 05.0s) |   C |    40 | 17.3 |        
     250 | 2022-03-30 12:31:59 |         MASTER-OAGH | (21h 20m 25.76s , +62d 48m 12.7s) |   C |    40 | 16.8 |        
     250 | 2022-03-30 12:31:59 |         MASTER-OAGH | (21h 21m 26.33s , +62d 19m 48.6s) |   C |    40 | 16.7 |        
     294 | 2022-03-30 12:32:38 |         MASTER-Amur | (21h 30m 55.02s , +63d 06m 11.5s) |   C |    50 | 17.4 |        
     321 | 2022-03-30 12:33:00 |         MASTER-OAGH | (21h 20m 31.69s , +62d 48m 40.7s) |   C |    60 | 16.6 |        
     321 | 2022-03-30 12:33:00 |         MASTER-OAGH | (21h 21m 32.12s , +62d 20m 15.8s) |   C |    60 | 16.7 |        
     373 | 2022-03-30 12:33:47 |         MASTER-Amur | (21h 30m 57.89s , +63d 07m 45.6s) |   C |    70 | 17.5 |        
     407 | 2022-03-30 12:34:21 |         MASTER-OAGH | (21h 20m 28.95s , +62d 50m 12.7s) |   C |    70 | 16.5 |        
     407 | 2022-03-30 12:34:21 |         MASTER-OAGH | (21h 21m 29.28s , +62d 21m 47.0s) |   C |    70 | 16.5 |        
     461 | 2022-03-30 12:35:20 |         MASTER-Amur | (21h 05m 02.96s , +64d 18m 58.6s) |   C |    60 | 17.9 |        
     494 | 2022-03-30 12:35:52 |         MASTER-OAGH | (21h 22m 29.00s , +62d 02m 47.9s) |   C |    60 | 16.0 |        
     494 | 2022-03-30 12:35:52 |         MASTER-OAGH | (21h 23m 27.73s , +61d 34m 24.7s) |   C |    60 | 16.1 |        
     541 | 2022-03-30 12:36:40 |         MASTER-Amur | (21h 23m 22.59s , +64d 18m 08.6s) |   C |    60 | 17.7 |        
     651 | 2022-03-30 12:38:00 |         MASTER-Amur | (21h 42m 47.22s , +63d 23m 04.0s) |   C |   120 | 17.6 |        
     801 | 2022-03-30 12:40:19 |         MASTER-Amur | (21h 42m 52.69s , +63d 23m 29.4s) |   C |   140 | 17.6 |        
     980 | 2022-03-30 12:42:59 |         MASTER-Amur | (21h 42m 49.87s , +63d 24m 48.3s) |   C |   180 | 17.9 |        
    1180 | 2022-03-30 12:46:18 |         MASTER-Amur | (21h 42m 49.23s , +63d 23m 25.5s) |   C |   180 | 17.9 |        
    1319 | 2022-03-30 12:49:38 |         MASTER-Amur | (21h 39m 38.66s , +64d 18m 08.5s) |   C |    60 | 17.6 |        
    1614 | 2022-03-30 12:54:33 |         MASTER-Amur | (22h 06m 40.37s , +63d 37m 11.9s) |   C |    60 | 17.7 |        
    1695 | 2022-03-30 12:55:54 |         MASTER-Amur | (21h 05m 10.51s , +64d 17m 49.2s) |   C |    60 | 17.7 |        
    1775 | 2022-03-30 12:57:14 |         MASTER-Amur | (21h 23m 30.29s , +64d 18m 09.6s) |   C |    60 | 17.8 |        
    1855 | 2022-03-30 12:58:33 |         MASTER-Amur | (21h 23m 42.97s , +66d 11m 54.8s) |   C |    60 | 17.8 |        
    1934 | 2022-03-30 12:59:53 |         MASTER-Amur | (21h 43m 20.23s , +66d 13m 51.1s) |   C |    60 | 17.5 |        
    2019 | 2022-03-30 13:01:18 |         MASTER-Amur | (21h 39m 36.72s , +60d 31m 51.9s) |   C |    60 | 17.4 |        
    2098 | 2022-03-30 13:02:37 |         MASTER-Amur | (21h 55m 45.97s , +60d 30m 58.6s) |   C |    60 | 17.2 |        
    2186 | 2022-03-30 13:04:05 |         MASTER-Amur | (21h 09m 09.99s , +60d 29m 32.5s) |   C |    60 | 17.5 |        
    2266 | 2022-03-30 13:05:25 |         MASTER-Amur | (21h 25m 10.42s , +60d 31m 07.0s) |   C |    60 | 17.3 |        
    2345 | 2022-03-30 13:06:44 |         MASTER-Amur | (21h 39m 48.03s , +64d 17m 49.7s) |   C |    60 | 17.6 |        
    2425 | 2022-03-30 13:08:04 |         MASTER-Amur | (21h 55m 09.06s , +62d 24m 47.8s) |   C |    60 | 17.3 |        
    2710 | 2022-03-30 13:12:48 |         MASTER-Amur | (22h 20m 25.56s , +61d 43m 08.3s) |   C |    60 | 17.3 |        
    2791 | 2022-03-30 13:14:10 |         MASTER-Amur | (21h 57m 59.57s , +64d 18m 09.6s) |   C |    60 | 17.4 |        
    2871 | 2022-03-30 13:15:30 |         MASTER-Amur | (21h 05m 15.11s , +64d 17m 22.6s) |   C |    60 | 17.8 |        
    2951 | 2022-03-30 13:16:50 |         MASTER-Amur | (21h 23m 24.84s , +64d 19m 03.6s) |   C |    60 | 17.7 |        
    3031 | 2022-03-30 13:18:10 |         MASTER-Amur | (21h 23m 40.35s , +66d 11m 48.7s) |   C |    60 | 17.8 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220331A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31808
SUBJECT: GRB 220331A: Fermi GBM Final Real-time Localization
DATE:    22/03/31 18:47:19 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 18:37:02 UT on 31 Mar 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220331A (trigger 670444627.268388 / 220331776).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 12.8, Dec = 2.9 (J2000 degrees, equivalent to J2000 00h 51m, 2d 53'), with a statistical uncertainty of 4.1 degrees.

The angle from the Fermi LAT boresight is 58.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220331776/quicklook/glg_skymap_all_bn220331776.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220331776/quicklook/glg_healpix_all_bn220331776.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220331776/quicklook/glg_lc_medres34_bn220331776.gif


GRB_name: GRB220401A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31811
SUBJECT: GRB 220401A: Fermi GBM Final Localization
DATE:    22/04/01 17:40:40 GMT
FROM:    Peter Veres at UAH  <veresp@gmail.com>

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

At 10:17:40.89 UT on 1 April 2022, the Fermi Gamma-ray Burst Monitor
(GBM) triggered and located GRB 220401A (trigger  670501065/
220401429). The trigger was initially classified as a Solar flare but
it is in fact a GRB.

The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 8.0, Dec = 50.0 (J2000 degrees, equivalent to J2000 0h 3m, 50d
00'), with a statistical uncertainty of 4.2 degrees.

The angle from the Fermi LAT boresight is 82.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220401429/quicklook/glg_skymap_all_bn220401429.png

The HEALPix FITS file, including the estimated localization
systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220401429/quicklook/glg_healpix_all_bn220401429.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220401429/quicklook/glg_lc_medres34_bn220401429.gif


GRB_name: GRB220401B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31812
SUBJECT: GRB 220401B: Fermi GBM Final Real-time Localization
DATE:    22/04/01 21:40:11 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 21:29:49 UT on 1 Apr 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220401B (trigger 670541394.48622 / 220401896).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 352.5, Dec = 42.9 (J2000 degrees, equivalent to J2000 23h 30m, 42d 53'), with a statistical uncertainty of 5.0 degrees.

The angle from the Fermi LAT boresight is 35.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220401896/quicklook/glg_skymap_all_bn220401896.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220401896/quicklook/glg_healpix_all_bn220401896.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220401896/quicklook/glg_lc_medres34_bn220401896.gif


GRB_name: GRB220401B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31813
SUBJECT: Fermi GRB 220401B: Global MASTER-Net observations report 
DATE:    22/04/02 00:30:34 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, D. Vlasenko, 
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(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. Gres, N.M. Budnev
(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),

A. Gabovich, V.Yurkov 
(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 220401B ( Fermi GBM team, GCN 31812) errorbox  6433 sec after notice time and 6465 sec after trigger time at 2022-04-01 23:17:35 UT, with upper limit up to  17.1 mag. The observations began at zenith distance = 79 deg. The sun  altitude  is -37.2 deg. 

The galactic latitude b = -17 deg., longitude l = 108 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1929659

We obtain a following upper limits.  

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

    6496 | 2022-04-01 23:17:35 |      MASTER-Tavrida | (23h 11m 07.09s , +48d 44m 33.2s) |   C |    60 | 15.8 |        
    6575 | 2022-04-01 23:18:54 |      MASTER-Tavrida | (23h 23m 11.16s , +48d 42m 51.3s) |   C |    60 | 15.2 |        
    7361 | 2022-04-01 23:32:00 |      MASTER-Tavrida | (23h 05m 26.06s , +46d 50m 36.7s) |   C |    60 | 16.1 |        
    7441 | 2022-04-01 23:33:20 |      MASTER-Tavrida | (23h 17m 04.52s , +46d 49m 09.2s) |   C |    60 | 15.9 |        
    7521 | 2022-04-01 23:34:40 |      MASTER-Tavrida | (23h 11m 12.74s , +48d 44m 00.8s) |   C |    60 | 16.5 |        
    7600 | 2022-04-01 23:35:59 |      MASTER-Tavrida | (23h 20m 04.91s , +48d 43m 37.2s) |   C |    60 | 15.6 |        
    7680 | 2022-04-01 23:37:19 |      MASTER-Tavrida | (23h 31m 02.95s , +48d 43m 40.8s) |   C |    60 | 15.5 |        
    8158 | 2022-04-01 23:45:17 |      MASTER-Tavrida | (23h 09m 43.90s , +44d 57m 08.3s) |   C |    60 | 16.0 |        
    8476 | 2022-04-01 23:50:35 |      MASTER-Tavrida | (23h 02m 23.18s , +46d 50m 15.2s) |   C |    60 | 16.8 |        
    8556 | 2022-04-01 23:51:55 |      MASTER-Tavrida | (23h 14m 02.06s , +46d 49m 02.9s) |   C |    60 | 16.6 |        
    8635 | 2022-04-01 23:53:14 |      MASTER-Tavrida | (23h 08m 08.92s , +48d 43m 56.8s) |   C |    60 | 16.9 |        
    8714 | 2022-04-01 23:54:33 |      MASTER-Tavrida | (23h 20m 07.49s , +48d 43m 25.0s) |   C |    60 | 16.3 |        
    8794 | 2022-04-01 23:55:53 |      MASTER-Tavrida | (23h 31m 01.03s , +48d 44m 27.0s) |   C |    60 | 16.1 |        
    8873 | 2022-04-01 23:57:12 |      MASTER-Tavrida | (23h 43m 10.22s , +48d 43m 30.6s) |   C |    60 | 15.4 |        
    9032 | 2022-04-01 23:59:51 |      MASTER-Tavrida | (22h 58m 35.49s , +44d 55m 08.8s) |   C |    60 | 16.4 |        
    9111 | 2022-04-02 00:01:10 |      MASTER-Tavrida | (23h 09m 48.29s , +44d 56m 28.6s) |   C |    60 | 16.4 |        
    9271 | 2022-04-02 00:03:50 |      MASTER-Tavrida | (23h 19m 52.95s , +44d 55m 51.3s) |   C |    60 | 16.4 |        
    9350 | 2022-04-02 00:05:09 |      MASTER-Tavrida | (23h 31m 07.29s , +44d 56m 57.7s) |   C |    60 | 16.0 |        
    9429 | 2022-04-02 00:06:28 |      MASTER-Tavrida | (23h 02m 26.20s , +46d 49m 30.5s) |   C |    60 | 16.9 |        
    9509 | 2022-04-02 00:07:48 |      MASTER-Tavrida | (23h 13m 59.57s , +46d 48m 31.5s) |   C |    60 | 16.9 |        
    9752 | 2022-04-02 00:11:51 |      MASTER-Tavrida | (23h 07m 17.41s , +43d 02m 48.0s) |   C |    60 | 16.6 |        
    9832 | 2022-04-02 00:13:11 |      MASTER-Tavrida | (23h 31m 08.40s , +48d 43m 17.3s) |   C |    60 | 16.7 |        
    9912 | 2022-04-02 00:14:31 |      MASTER-Tavrida | (23h 43m 05.75s , +48d 42m 20.0s) |   C |    60 | 16.4 |        
    9991 | 2022-04-02 00:15:50 |      MASTER-Tavrida | (22h 58m 35.99s , +44d 54m 54.0s) |   C |    60 | 17.1 |        
   10070 | 2022-04-02 00:17:09 |      MASTER-Tavrida | (23h 09m 49.83s , +44d 56m 20.4s) |   C |    60 | 17.1 |        
   10150 | 2022-04-02 00:18:29 |      MASTER-Tavrida | (23h 17m 11.74s , +43d 02m 16.9s) |   C |    60 | 16.7 |        
   10229 | 2022-04-02 00:19:48 |      MASTER-Tavrida | (23h 28m 01.20s , +43d 01m 49.4s) |   C |    60 | 16.1 |        
   10309 | 2022-04-02 00:21:08 |      MASTER-Tavrida | (23h 19m 55.45s , +44d 56m 35.0s) |   C |    60 | 17.1 |        
   10388 | 2022-04-02 00:22:27 |      MASTER-Tavrida | (23h 31m 17.24s , +44d 55m 39.2s) |   C |    60 | 16.6 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220401A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31816
SUBJECT: GRB 220401A: Fermi GBM observation
DATE:    22/04/02 13:25:43 GMT
FROM:    Peter Veres at UAH  <veresp@gmail.com>

P. Veres (UAH), E. Bissaldi (Politecnico and INFN Bari) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 10:17:40.89 UT on 1 April 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 220401A (trigger 670501065 / 220401429).

The localization was reported in GCN 31811.

The GBM lightcurve consists of two emission episodes
with a duration (T90) of about 39.2 s (50-300 keV).
The time-averaged spectrum from T0-8.2 s to T0+38.9 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.37 +/- 0.08
 and the cutoff energy, parameterized as Epeak, is 46 +/- 2 keV.

The event fluence (10-1000 keV) in this time interval is
(2.42 +/- 0.06)E-6 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+7.0 s in the 10-1000 keV band
is 7.8 +/- 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: GRB220401A
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31817
SUBJECT: GRB 220401A: Swift/BAT-GUANO detection outside the coded FOV
DATE:    22/04/02 22:50:45 GMT
FROM:    Aaron Tohuvavohu at U Toronto  <aaron.tohu@gmail.com>

Gayathri Raman (PSU), Aaron Tohuvavohu (U Toronto), James DeLaunay
(UAlabama), Jamie A. Kennea (PSU), report:

Swift/BAT did not localize GRB 220401A onboard (T0: 2022-04-01T10:17:40
 UTC, Fermi/GBM GCN 31811, 31816).

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,
arXiv:2111.01769), detects the burst with a sqrt(TS) of 10.1 in a
1.024 s analysis time bin.

Only the peak of the second emission episode (at ~T0+35s) is clearly
detected in BAT.

NITRATES results are consistent with a burst coming from outside the
coded FoV, as indicated by the Fermi/GBM localization (GCN 31816).

See Section 9.1 and Figure 20 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: GRB220403A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31818
SUBJECT: GRB 220403A: Fermi GBM Final Real-time Localization
DATE:    22/04/03 10:21:18 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 10:10:02 UT on 3 Apr 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220403A (trigger 670673407.661128 / 220403424).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 56.5, Dec = -44.3 (J2000 degrees, equivalent to J2000 03h 46m, -44d 17'), with a statistical uncertainty of 15.3 degrees.

The angle from the Fermi LAT boresight is 14.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220403424/quicklook/glg_skymap_all_bn220403424.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220403424/quicklook/glg_healpix_all_bn220403424.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220403424/quicklook/glg_lc_medres34_bn220403424.gif


GRB_name: GRB220403A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31819
SUBJECT: Fermi GRB 220403A: Global MASTER-Net observations report 
DATE:    22/04/03 20:30:33 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, D. Vlasenko, 
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(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. Gres, N.M. Budnev
(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),

A. Gabovich, V.Yurkov 
(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 220403A ( Fermi GBM team, GCN 31818) errorbox  25928 sec after notice time and 25957 sec after trigger time at 2022-04-03 17:22:40 UT, with upper limit up to  19.0 mag. Observations started at twilight.  The observations began at zenith distance = 40 deg. The sun  altitude  is -11.4 deg. 

The galactic latitude b = -51 deg., longitude l = 251 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1931107

We obtain a following upper limits.  

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

   25988 | 2022-04-03 17:22:40 |         MASTER-SAAO | (04h 20m 06.06s , -55d 00m 19.5s) |   V |    60 | 17.1 |        
   26067 | 2022-04-03 17:23:59 |         MASTER-SAAO | (04h 20m 11.62s , -55d 00m 16.9s) |   C |    60 | 17.3 |        
   26931 | 2022-04-03 17:38:24 |         MASTER-SAAO | (04h 20m 10.16s , -54d 59m 21.9s) |   V |    60 | 17.2 |        
   27011 | 2022-04-03 17:39:44 |         MASTER-SAAO | (04h 20m 13.25s , -54d 58m 04.9s) |   C |    60 | 17.7 |        
   32778 | 2022-04-03 19:15:50 |         MASTER-SAAO | (04h 16m 32.90s , -29d 11m 52.6s) |   C |    60 | 18.4 |        
   32858 | 2022-04-03 19:17:10 |         MASTER-SAAO | (04h 25m 45.28s , -29d 10m 01.4s) |   C |    60 | 19.0 |        
   33896 | 2022-04-03 19:34:28 |         MASTER-SAAO | (04h 16m 37.18s , -29d 11m 05.9s) |   C |    60 | 18.0 |        
   33976 | 2022-04-03 19:35:48 |         MASTER-SAAO | (04h 25m 49.01s , -29d 09m 49.4s) |   C |    60 | 18.5 |        
   34928 | 2022-04-03 19:51:41 |         MASTER-SAAO | (04h 16m 45.67s , -29d 10m 04.1s) |   C |    60 | 17.5 |        
   35008 | 2022-04-03 19:53:00 |         MASTER-SAAO | (04h 25m 46.29s , -29d 10m 59.4s) |   C |    60 | 18.1 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220403B
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31820
SUBJECT: GRB 220403B: Swift detection of a burst with an optical counterpart
DATE:    22/04/03 20:54:46 GMT
FROM:    Hans Krimm at NSF/NASA-GSFC  <hkrimm@nsf.gov>

N. J. Klingler (GSFC/UMBC/CRESSTII), E. Ambrosi (INAF-IASFPA),
V. D'Elia (SSDC & INAF-OAR), S. Dichiara (PSU), J.D. Gropp (PSU),
H. A. Krimm (NSF), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL),
T. M. Parsotan (GSFC/UMBC/CRESSTII) and T. Sakamoto (AGU) report on
behalf of the Neil Gehrels Swift Observatory Team:

At 20:42:42 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 220403B (trigger=1101053).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 191.025, +89.170 which is 
   RA(J2000) = 12h 44m 06s
   Dec(J2000) = +89d 10' 13"
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 30 sec and a possible precursor just before. 
The peak count rate was ~2800 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 20:44:18.9 UT, 96.3 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 191.50031, 89.18362 which
is equivalent to:
   RA(J2000)  = 12h 46m 00.07s
   Dec(J2000) = +89d 11' 01.0"
with an uncertainty of 3.9 arcseconds (radius, 90% containment). This
location is 54 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. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 1.20
x 10^21 cm^-2 (Willingale et al. 2013). 

The initial flux in the 2.5 s image was 4.65e-10 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 105 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 12:45:53.30 = 191.47207
  DEC(J2000) = +89:11:06.6  =  89.18518
with a 90%-confidence error radius of about 0.67 arc sec. This position is 6.0
arc sec. from the center of the XRT error circle. The estimated magnitude is
19.80 with a 1-sigma error of about  0.17. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.208. 

Burst Advocate for this burst is N. J. Klingler (noelklin AT umbc.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: GRB220403B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31821
SUBJECT: GRB 220403B: optical detection by D50
DATE:    22/04/03 22:14:20 GMT
FROM:    Martin Jelinek at Astro.Inst-AVCR,Ondrejov  <martin.jelinek@asu.cas.cz>

M. Jelinek, J. Strobl, R. Hudec, C. Polasek (ASU CAS Ondrejov) report:

We observed the position of the Swift-detected GRB 220403B (Klingler et
al. GCNC 31820) with the D50 telescope of the Astronomical Institute
Ondrejov, near Prague, Czech Republic. Our observation started at 21:04 UT,
i.e. 22 min after the initial trigger and was performed without a filter.

We detect the optical afterglow (Klingler et al. GCNC 31820) in a combined
image with exp. mean time 31.3 min after trigger (exposed 21:05--21:22UT)
with an AB magnitude RC = 19.02 +/- 0.04.


GRB_name: GRB220403A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31822
SUBJECT: GRB 220403A: Tautenburg observations
DATE:    22/04/03 22:57:37 GMT
FROM:    Ana Nicuesa at TLS Tautenburg  <ana@tls-tautenburg.de>

A. Nicuesa Guelbenzu, B. Stecklum, S. Klose, S. Melnikov, and
U. Ludwig (all Tautenburg) report:

Tautenburg started observing the field of GRB 220403A (Klingler et
al. GCN 31820) at 2022-04-03, 21:35:37 UT, using the 1.34m Schmidt
telescope equipped with the TAUKAM 6k x 6k CCD camera. Observations
are still ongoing.

At a mean time 21:36:07 UT for the optical transient discovered by
Swift/UVOT, we measure the following magnitude:

r = 19.28 +/- 0.04 mag (AB),

calibrated against the Pan-STARRS catalog. Compared to the observations
reported by Jelinek et al. (GCN 31821), the source is fading.


GRB_name: GRB220403B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31823
SUBJECT: GRB 220403B: Nanshan/NEXT optical afterglow power-law decay
DATE:    22/04/03 23:17:19 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

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

We observed the field of GRB 220403B detected by Swift (Klingler et al., 
GCN 31820) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, 
China. Observations started at 21:10:31 UT on 2022-04-03 (i.e., 27.8 min 
after the BAT trigger), and a series of 300 s frames were obtained in 
the Sloan r-filters.

The optical afterglow (Klingler et al., GCN 31820) is clearly detected 
in each of our images. The preliminary photometric analysis shows that 
the afterglow decays from r ~ 19.04 to r ~ 19.64 in 47 minutes, with a 
decay index of \alpha ~ 0.6 (F_t ~ t^-\alpha), calibrated the nearby PS1 
stars.

Our measurement is consistent with that in other reports (Jelinek et 
al., GCN 31821; Nicuesa Guelbenzu et al., GCN 31822).


GRB_name: GRB220403C
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31824
SUBJECT: GRB 220403C (or A): Swift/BAT-GUANO detection outside the coded FOV
DATE:    22/04/04 01:46:45 GMT
FROM:    Aaron Tohuvavohu at U Toronto  <aaron.tohu@gmail.com>

Aaron Tohuvavohu (U Toronto), Gayathri Raman (PSU), James DeLaunay
(UAlabama), Jamie A. Kennea (PSU), report:

Swift/BAT did not localize GRB 220403C onboard (T0: 2022-04-03T10:13:50
 UTC, INTEGRAL SPI/ACS trig #9822 CALET trig #1333015963).

The INTEGRAL and CALET 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 90 seconds of BAT event-mode data from
[-45,+45] 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,
arXiv:2111.01769), detects the burst with a sqrt(TS) of 224.4 in a
8.192 s analysis time bin.
The burst episode as seen by BAT is ~15s long.

NITRATES results strongly indicate a burst coming from outside the
coded FoV, with DeltaLLHOut of -1614.

See Section 9.1 and Figure 20 in the NITRATES paper for brief
descriptions and interpretation of sqrt(TS), DeltaLLHPeak, and
DeltaLLHOut.

GUANO was also triggered by notice of GRB 220403A, detected by
Fermi/GBM with T0: 2022-04-03T10:10:02 UTC (GCN 31818).
GUANO retrieved 200s of event data from [-50,+150] seconds around the
time of the burst. This Fermi/GBM trigger was 228 seconds before the
emission episode reported above.

This burst is not detected by NITRATES running on the BAT-GUANO data.

The peak flux of the first emission episode in Fermi/GBM is
substantially weaker compared to that seen for the second in BAT, and
its non-detection in the BAT data is not necessarily indicative of a
different progenitor object, especially considering the OFOV origin.

GRB 220403A could be a weak precursor episode to GRB 220403C, produced
by the same object. Enhanced localizations for both bursts will be
required to determine their relationship, if any.

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: GRB220403B
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31825
SUBJECT: Swift GRB 220403B: Global MASTER-Net observations report 
DATE:    22/04/04 02:37:02 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, D. Vlasenko, 
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(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. Gres, N.M. Budnev
(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),

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


MASTER-OAGH robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) was pointed to the Swift GRB 220403B ( N. J. Klingler et al., GCN 31820) errorbox  20759 sec after notice time and 20778 sec after trigger time at 2022-04-04 02:29:01 UT, with upper limit up to  17.7 mag. Observations started at twilight.  The observations began at zenith distance = 59 deg. The sun  altitude  is -11.3 deg. 

The galactic latitude b = 28 deg., longitude l = 123 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1931497

We obtain a following upper limits.  

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

   20869 |         MASTER-OAGH |   C |   180 | 17.2 |        
   20869 |         MASTER-OAGH |   C |   180 | 17.7 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220403B
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31826
SUBJECT: GRB 220403B: LBT observations
DATE:    22/04/04 06:11:24 GMT
FROM:    Andrea Rossi at INAF  <andrea.rossi@inaf.it>

A Rossi (INAF-OAS) report on behalf of the CIBO collaboration:

We observed the field of GRB 220403B (Klingler et al., GCN 31820) 
simultaneously in the g',r',i' and z' bands with the LBC imager mounted 
on LBT (Mt Graham, AZ, USA). We obtained 10min of imaging at the midtime 
04:02 UT on 2022-04-04, 0.3 days after the burst trigger. Observations 
were performed under good weather conditions with an average seeing of 
~1.5".

We clearly detect the afterglow and we preliminary measure

r=20.9+-0.1 (AB system),

calibrated against Pan-STARRS field stars.

We acknowledge the excellent support from the LBTO and LBT-INAF staff, 
particularly A. Cardwell and S. Allanson in obtaining these observations.


GRB_name: GRB220403B
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31827
SUBJECT: GRB 220403B: Swift-XRT refined Analysis
DATE:    22/04/04 07:08:18 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), E. Ambrosi 
(INAF-IASFPA) , M. Capalbi (INAF-IASFPA), M. Perri (SSDC & INAF-OAR),
A. Tohuvavohu (U. Toronto), B. Sbarufatti (PSU), D.N. Burrows (PSU),
J.P. Osborne (U. Leicester) and N.J. Klingler report on behalf of the
Swift-XRT team:

We have analysed 6.3 ks of XRT data for GRB 220403B (Klingler et al.
GCN Circ. 31820), from 86 s to 28.9 ks after the  BAT trigger. The data
comprise 50 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 refined XRT position is RA, Dec = 191.4734, +89.1846 which is
equivalent to:

RA (J2000): 12 45 53.62
Dec(J2000): +89 11 04.6

with an uncertainty of 3.5 arcsec (radius, 90% confidence).

The light curve can be modelled with an initial power-law decay with an
index of alpha=4.4 (+/-0.4), followed by a break at T+229 s to an alpha
of 0.35 (+0.04, -0.05).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.86 (+0.16, -0.14). The
best-fitting absorption column is  1.47 (+0.51, -0.27) x 10^21 cm^-2,
consistent with the Galactic value of 1.2 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 3.7 x 10^-11 (4.6 x
10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.47 (+0.51, -0.27) x 10^21 cm^-2
Galactic foreground: 1.2 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index:      1.86 (+0.16, -0.14)

If the light curve continues to decay with a power-law decay index of
0.35, the count rate at T+24 hours will be 0.057 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.1 x
10^-12 (2.6 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/01101053.

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


GRB_name: GRB220404A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31828
SUBJECT: GRB 220404A: Swift detection of a burst
DATE:    22/04/04 12:07:35 GMT
FROM:    Kim Page at U.of Leicester  <kimlpage1978@gmail.com>

S. B. Cenko (GSFC), V. D'Elia (SSDC & INAF-OAR), S. Dichiara (PSU),
J.D. Gropp (PSU), K. L. Page (U Leicester) and
T. M. Parsotan (GSFC/UMBC/CRESSTII) report on behalf of the Neil
Gehrels Swift Observatory Team:

At 11:54:30 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 220404A (trigger=1101133). 
The BAT on-board calculated location is 
RA, Dec 50.448, +10.005 which is 
   RA(J2000) = 03h 21m 47s
   Dec(J2000) = +10d 00' 16"
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 10 sec.  The peak count rate
was ~1200 counts/sec (15-350 keV), at ~2 sec after the trigger. 

Due to a Sun observing constraint, Swift cannot slew to the BAT
position until 20:40 UT on 2022 June 28. There will thus be no XRT or
UVOT data for this trigger before this time. 

Burst Advocate for this burst is S. B. Cenko (brad.cenko AT nasa.gov). 
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: GRB220403B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31829
SUBJECT: GRB 220403B: Fermi GBM detection
DATE:    22/04/04 15:12:37 GMT
FROM:    Rachel Hamburg at UAH  <rkh0007@uah.edu>

Rachel Hamburg (UAH) and Boyan Hristov (UAH)
report on behalf of the Fermi GBM Team:

"At 20:42:39.05 UT on 03 April 2022, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 220403B (trigger 670711364 / 220403863), which
was also detected by the Swift/BAT and the Swift/XRT (Klingler et al. 2022,
GCN 31820). Additionally, the optical afterglow was detected by the
Swift/UVOT (Klingler et al. 2022, GCN 31820), D50 (Jelinek et al. 2022,
GCN 31821), Nanshan/NEXT (Zhu et al. 2022, GCN 31823) and LBT (Rossi 2022,
GCN 31826).

The angle from the Fermi LAT boresight at the GBM trigger time is 43
degrees.

The GBM light curve shows broad rise with multiple peaks with a
duration (T90) of about 28 s (50-300 keV).

The time-averaged spectrum from T0-6.1 s to T0+21.5 s is best fit by a
power law function with an exponential high-energy cutoff. The power law
index is -1.2 +/- 0.1 and the cutoff energy, parameterized as Epeak,
is 79 +/- 3 keV. The spectrum is also well fit by a Band function with
Epeak = 70 +/- 5, alpha = -1.1 +/- 0.1, and beta = -2.6 +/- 0.2.

The event fluence (10-1000 keV) in this time interval is
(5.2 +/- 0.1)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+7.6 s in the 10-1000 keV band is 4.3 +/- 0.2 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: GRB220403B
Detection_method: correction
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31830
SUBJECT: GRB 220403B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
DATE:    22/04/04 17:28:51 GMT
FROM:    Toktarkhan Komesh at Nazarbayev University  <toktarkhan.komesh@nu.edu.kz>

SUBJECT: GRB 220403B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)

B. Grossan (UCB, NU), T. Komesh (NU), Z. Maksut (NU), M. Krugov (FAI), E. Linder (UCB, NU), E. Abdikamalov (NU), K. Baigarin (NU), G. F. Smoot (HKUST, UCB, NU), report on behalf of the Energetic Cosmos Laboratory:

The Nazarbayev University Transient Telescope at Assy-Turgen Astrophysical Observatory (NUTTelA-TAO) observed the field of GRB 220403B 11 s after receipt an automated GCN / BAT position alert, observing in Sloan i' band, with the Burst Simultaneous Three-Channel Imager (BSTI; Grossan, Kumar & Smoot 2019, JHEA, 32, 14).

We started observations at 20:43:09 UT on 2022-04-03, 27 s after the BAT trigger. Observations were made in partially cloudy conditions starting at about 43 deg. target altitude. No source consistent with the XRT (A.P. Beardmore et al., GCN Circ.31827) was detected.  We report the following results:

start time  t-t0(s)  end time        ULi'       exposure_time (s)
---------  ----   ---------        ------     --------------------
20:43:09     27   20:44:09          17.6           60
20:44:24     87   20:46:54          18.4           150

start time is in UT. t-t0(s) gives the time since trigger, in seconds. UL i', gives the 5 sigma upper limit sensitivity in magnitudes, for images co-added to the given exposure time. The first row in the table corresponds to co-adds of an initial short exposure image sequence of 7.5 s. The second row corresponds to co-adds from a continuing series of 15 s exposures.  Calibration was done with the 2 bright Pan-STARRS catalog stars on our images.

We caution the reader that these are preliminary results, without color or other corrections. Please also note that times are approximate.
----------------------------------
NU = Nazarbayev University, Nur-Sultan, Kazakhstan
UCB = University of California, Berkeley, USA
HKUST = Hong Kong University of Science and Technology
FAI = Fesenkov Astrophysical Institute, Kazakhstan

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: GRB220404B
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31831
SUBJECT: GRB 220404B: Fermi GBM Final Real-time Localization
DATE:    22/04/04 17:59:07 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 17:47:23 UT on 4 Apr 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220404B (trigger 670787248.326908 / 220404741).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 25.6, Dec = -10.8 (J2000 degrees, equivalent to J2000 01h 42m, -10d 48'), with a statistical uncertainty of 7.5 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/2022/bn220404741/quicklook/glg_skymap_all_bn220404741.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220404741/quicklook/glg_healpix_all_bn220404741.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220404741/quicklook/glg_lc_medres34_bn220404741.gif


GRB_name: GRB220403B
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31834
SUBJECT: GRB 220403B: Swift-BAT refined analysis
DATE:    22/04/05 13:29:33 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto@phys.aoyama.ac.jp>

A. Y. Lien (U Tampa), S. D. Barthelmy (GSFC), N. J. Klingler (GSFC/UMBC/CRESSTII)
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), 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 220403B (trigger #1101053)
(Klingler, et al., GCN Circ. 31820).  The BAT ground-calculated position is
RA, Dec = 190.974, 89.180 deg which is
    RA(J2000)  =  12h 43m 53.9s
    Dec(J2000) = +89d 10' 49.0"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 60%.

The mask-weighted light curve shows a bright peak structure that starts
at T-19 s, peaks at T-1 s and ends at T+40 s.  T90 (15-350 keV) is
27.0 +- 3.4 sec (estimated error including systematics).
  
The time-averaged spectrum from T-14.42 to T+27.96 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.94 +- 0.06.  The fluence in the 15-150 keV band is 3.7 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+1.06 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/1101053/BA/


GRB_name: GRB220405A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31835
SUBJECT: GRB 220405A: Fermi GBM Final Localization
DATE:    22/04/05 15:43:46 GMT
FROM:    Elisabetta Bissaldi at INFN,Bari  <elisabetta.bissaldi@ba.infn.it>

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

At 06:11:39.12 UT on 5 Apr 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220405A (trigger 670831904.120598 / 220405258).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 29.4, Dec = -22.8 (J2000 degrees, equivalent to J2000 01h 57m, -22d 48'), with a statistical uncertainty of 1.2 degrees.

The angle from the Fermi LAT boresight is 18.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220405258/quicklook/glg_skymap_all_bn220405258.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220405258/quicklook/glg_healpix_all_bn220405258.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220405258/quicklook/glg_lc_medres34_bn220405258.gif


GRB_name: GRB220403B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31837
SUBJECT: GRB 220403B: Kitab optical observations
DATE:    22/04/05 21:24:30 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

N. Pankov (HSE), A. Zhornichenko (KIAM), A. Pozanenko (IKI), V. 
Agletdinov (KIAM), S. Belkin (IKI), Sh. Ehgamberdiev (UBAI) report on 
behalf of IKI-GRB-FuN:

We observed the field of  GRB 220403B  (Klingler  et al., GCN 31820) 
with Kitab RC-36  telescope in Clear filter.  Observation started on 
April, 03  (UT) 21:23:55 and ended on April, 04 (UT) 00:00:11. We 
clearly detect the optical afterglow (Klingler  et al., GCN  31820; 
Jelinek  et al., GCN 31821; Zhu  et al., GCN 31823; Rossi  et al., GCN 
31826; see also early upper limits in Lipunov et al., GCN 31825; Grossan 
  et al., GCN 31830) in the combined images of an initial part of 
observations and do not detect it in the final part.
Preliminary photometry of the  combined images is following

  Date,      UT start, t-T0,   Exp.,  Filter, OT,    Err,  UL(3 sigma)
                     (mid, days)

2022-04-03  21:23:55 0.05178   40*60  CR      19.24  0.19   20.2
2022-04-03  22:30:39 0.10640   87*60  CR      n/d    n/d    20.5

The photometry is based on nearby USNO-B1.0 stars, R2 magnitude
USNO-B1.0_id R2
1791-0003982 16.77
1791-0003984 17.83


GRB_name: GRB220404A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31838
SUBJECT: GRB 220404A: Swift-BAT refined analysis
DATE:    22/04/06 01:13:25 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto@phys.aoyama.ac.jp>

C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), S. B. Cenko (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), 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 220404A (trigger #1101133)
(Cenko, et al., GCN Circ. 31828).  The BAT ground-calculated position is
RA, Dec = 50.413, 10.001 deg which is
   RA(J2000)  =  03h 21m 39.0s
   Dec(J2000) = +10d 00' 03.4"
with an uncertainty of 2.7 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 47%.

The mask-weighted light curve shows a weak peak starts at T0 and ends at
T+3 s.  There is a hint of a emission around T+5 s. T90 (15-350 keV) is
2.54 +- 0.66 sec (estimated error including systematics).

The time-averaged spectrum from T+0.26 to T+2.98 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.90 +- 0.36.  The fluence in the 15-150 keV band is 1.4 +- 0.3 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+1.15 sec in the 15-150 keV band
is 1.1 +- 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/1101133/BA/


GRB_name: GRB220403B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31841
SUBJECT: GRB 220403B: 1.5m OSN optical observation
DATE:    22/04/06 11:59:32 GMT
FROM:    Youdong HU at IAA-CSIC  <huyoudong072@hotmail.com>

Y.-D. Hu, A. Sota, A. J. Castro-Tirado, T.-R. Sun, M. D. Caballero-Garcia, R. Sanchez-Ramirez and E. Fernandez-Garcia (IAA-CSIC), on behalf of a larger collaboration, report:

Following the detection of GRB 220403B by Swift (Klingler et al. GCNC 31820) and Fermi (Hamburg et al. GCNC 31829), we triggered the 1.5m OSN telescope in Granada (Spain) starting on Apr 4 at 02:49 UT (i.e. ~6.1 h post burst). A series of images in the I band with 60 s exposure were obtained in cloudy weather. In the co-added image of selected high S/N frames, the optical afterglow is weakly detected within the position reported by UVOT (Klingler et al. GCNC 31820) and XRT (Beardmore et al. GCNC 31827) with I=20.45+-0.30 at a median time of 03:20 UT, which is consistent with previous reports of detection by Jelinek et al. (GCNC 31821), Zhu et al. (GCNC 31823), Rossi et al. (GCNC 31826) and Pankov et al. (GCNC 31837), also upper limits by Lipunov et al. (GCNC 31825), Grossan et al. (GCNC 31830). Further observations are ongoing.

We thank the staff at OSN for their excellent support.


GRB_name: GRB220403B
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31844
SUBJECT: GRB 220403B: Mondy optical upper limit
DATE:    22/04/06 16:37:01 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed the field of  GRB 220403B  (Klingler  et al., GCN 31820) 
with AZT-33 telescope of Mondy observatory starting on April, 05  (UT) 
15:00:54.   We do not detect the optical afterglow (Klingler  et al., 
GCN  31820; Jelinek  et al., GCN 31821; Zhu  et al., GCN 31823; Rossi 
et al., GCN 31826; Pankov et al., GCN 31837; Hu et al., GCN 31841; see 
also early upper limits in Lipunov et al., GCN 31825; Grossan  et al., 
GCN 31830) in the combined image.
Preliminary photometry of the  combined image is following

  Date,      UT start, t-T0,   Exp.,  Filter, OT,    Err,  UL(3 sigma)
                     (mid, days)

2022-04-05  15:00:54 1.77723   20*120  R      n/d    n/d    23.2

The photometry is based on nearby USNO-B1.0 stars, R2 magnitude
USNO-B1.0_id R2
1791-0003982 16.77
1791-0003984 17.83


GRB_name: GRB220408A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31847
SUBJECT: GRB 220408A: Fermi GBM Final Real-time Localization
DATE:    22/04/08 05:56:20 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 05:46:04 UT on 8 Apr 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220408A (trigger 671089569.40531 / 220408240).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 192.9, Dec = 49.7 (J2000 degrees, equivalent to J2000 12h 51m, 49d 42'), with a statistical uncertainty of 6.5 degrees.

The angle from the Fermi LAT boresight is 52.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220408240/quicklook/glg_skymap_all_bn220408240.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220408240/quicklook/glg_healpix_all_bn220408240.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220408240/quicklook/glg_lc_medres34_bn220408240.gif


GRB_name: GRB220408A
Detection_method: Swift Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31848
SUBJECT: GRB 220408A: Swift detection of a burst with an optical counterpart, possibly associated with M51
DATE:    22/04/08 06:04:40 GMT
FROM:    Kim Page at U.of Leicester  <kimlpage1978@gmail.com>

R. Caputo (GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL),
B. Sbarufatti (PSU) and A. Tohuvavohu (U Toronto) report on behalf of
the Neil Gehrels Swift Observatory Team:

At 05:46:04 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 220408A (trigger=1101675).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 202.402, +47.061 which is 
   RA(J2000) = 13h 29m 36s
   Dec(J2000) = +47d 03' 41"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a double-peaked
structure with a duration of about 5 sec.  The peak count rate
was ~3500 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 05:47:53.1 UT, 109.0 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 202.41670, 47.06870 which is equivalent
to:
   RA(J2000)  = 13h 29m 40.01s
   Dec(J2000) = +47d 04' 07.3"
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This
location is 45 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. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (1.98 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 4.6
(+4.76/-3.79) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 112 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
  RA(J2000)  = 13:29:39.72 = 202.41548
  DEC(J2000) = +47:04:09.5  =  47.06931
with a 90%-confidence error radius of about 0.91 arc sec. This position is 5.1
arc sec. from the center of the XRT error circle. The estimated magnitude is
20.76 with a 1-sigma error of about  0.22. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.042. 

We note that this GRB is in a direction near to that of M51, the 
Whirlpool Galaxy, although well outside of its optical disk. 
Determining whether this is a coincidence will require further study. 

Burst Advocate for this burst is R. Caputo (regina.caputo AT nasa.gov). 
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: GRB220408A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31849
SUBJECT: Fermi GRB 220408A: Global MASTER-Net observations report 
DATE:    22/04/08 07:15:22 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, D. Vlasenko, 
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(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. Gres, N.M. Budnev
(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),

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


MASTER-OAGH robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) started inspect of the Fermi GRB 220408A ( Fermi GBM team, GCN 31847) errorbox  3978 sec after notice time and 4007 sec after trigger time at 2022-04-08 06:52:52 UT, with upper limit up to  17.7 mag. The observations began at zenith distance = 18 deg. The sun  altitude  is -51.3 deg. 

The galactic latitude b = 68 deg., longitude l = 122 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1936539

We obtain a following upper limits.  

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

    4098 | 2022-04-08 06:52:52 |         MASTER-OAGH | (13h 25m 40.01s , +47d 07m 29.9s) |   C |   180 | 16.5 |        
    4098 | 2022-04-08 06:52:52 |         MASTER-OAGH | (13h 26m 12.76s , +46d 40m 00.5s) |   C |   180 | 17.7 |        
    4299 | 2022-04-08 06:56:13 |         MASTER-OAGH | (13h 25m 46.29s , +47d 06m 27.0s) |   C |   180 | 15.9 |        
    4299 | 2022-04-08 06:56:13 |         MASTER-OAGH | (13h 26m 19.51s , +46d 38m 57.5s) |   C |   180 | 17.4 |        
    4501 | 2022-04-08 06:59:35 |         MASTER-OAGH | (13h 25m 41.42s , +47d 05m 24.8s) |   C |   180 | 16.2 |        
    4501 | 2022-04-08 06:59:35 |         MASTER-OAGH | (13h 26m 14.91s , +46d 37m 55.1s) |   C |   180 | 17.7 |        
    4702 | 2022-04-08 07:02:56 |         MASTER-OAGH | (13h 25m 46.46s , +47d 05m 45.0s) |   C |   180 | 16.6 |        
    4702 | 2022-04-08 07:02:56 |         MASTER-OAGH | (13h 26m 19.98s , +46d 38m 15.0s) |   C |   180 | 17.7 |        
    4904 | 2022-04-08 07:06:18 |         MASTER-OAGH | (13h 25m 43.83s , +47d 06m 57.3s) |   C |   180 | 16.7 |        
    4904 | 2022-04-08 07:06:18 |         MASTER-OAGH | (13h 26m 17.35s , +46d 39m 27.8s) |   C |   180 | 17.7 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220408A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31850
SUBJECT: GRB 220408A: KAIT Optical Observations
DATE:    22/04/08 09:02:14 GMT
FROM:    Weikang Zheng at UC Berkeley  <weikang@berkeley.edu>

WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:

The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to the Swift GRB 220408A (Caputo et al.,
GCN 31848; see also Fermi/GBM detection, GCN 31847) starting at
06:30:47 UT, ~44 min after the burst. Observations were performed
with a sequence in the clear (roughly R), V, and I filters, and the
exposure time was 20s per image. We did not detect the optical afterglow
reported by UVOT (Caputo et al., GCN 31848) in any of our single images.
We marginally detected the afterglow in the coadd image in clear band,
which we measured its brightness of 21.4 +/- 0.3 mag at ~53 min after the
burst, calibrated to the Pan-STARRS1 catalog.


GRB_name: GRB220408A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31851
SUBJECT: Chandra upper limit at the location of GRB 220408A
DATE:    22/04/08 10:23:23 GMT
FROM:    Sergio Campana at INAF-OAB  <sergio.campana@brera.inaf.it>

S. Campana (INAF - Osservatorio astronomico di Brera) reports

that Chandra serendipitously observed the location of GRB 220408A 
(Caputo et al. 2022, GCN 31848; Fermi team 2022, GCN 31847).
The UVOT position (Caputo et al. 2022) falls at the edge of the S4 chip 
of ACIS-S. The obsid 23474 observation lasted 36.6 ks and was taken on 
Dec 21, 2020.
No source is visible at this position.
We run srcflux (under CIAO 4.13 and CALDB 4.9.7) and derive a 3-sigma 
upper limit of 0.000206 c/s (2.38E-05,0.000432) on the 0.5-7 keV count 
rate. Assuming a power law photon index of 2 and a column density of 
2x10^20 cm^-2, we derive an upper limit on the 0.5-7 keV unabsorbed flux 
of 2.1e-14 erg/cm2/s.
If the GRB were at the M51 distance (8.58 Mpc), this translates into an 
upper limit on the 0.5-7 keV luminosity of 1.8e38 erg/s.


GRB_name: GRB220408A
Detection_method: Swift-XRT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31852
SUBJECT: GRB 220408A: Enhanced Swift-XRT position
DATE:    22/04/08 11:09:55 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.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 1138 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 220408A, 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 = 202.41658, +47.06912 which is equivalent
to:

RA (J2000): 13h 29m 39.98s
Dec (J2000): +47d 04' 08.8"

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: GRB220408A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31853
SUBJECT: GRB 220408A: Xinglong-2.16m optical upper limit
DATE:    22/04/08 13:30:31 GMT
FROM:    Dong Xu at NAOC/CAS  <dxu@nao.cas.cn>

S.Q. Jiang, S.Y. Fu, X. Liu, D. Xu (NAOC), Z.P. Zhu (NAOC, HUST), L.P. 
Xin, J.Y. Wei, G.W. Li (NAOC) report on behalf of a larger collaboration:

We observed the field of GRB 220408A detected by Swift (Caputo et al., 
GCN 31848) and Fermi (Fermi GBM team, GCN 31847) using the 
Xinglong-2.16m telescope equipped with the BFOSC camera. Observations 
were carried out starting at 12:02:32 UT on 2022-04-08 (i.e., 6.27 hr 
since the BAT trigger), and 9x400 s frames in the R-band were obtained.

The previously reported optical counterpart (e.g., Caputo et al., GCN 
31848; Zheng & Filippenko, GCN 31850) is not detected in our stacked 
image, down to a limiting magnitude of R ~ 20.7 (Vega) at 6.79 hr 
post-burst, calibrated with the nearby SDSS field.


GRB_name: GRB220408B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31854
SUBJECT: GRB 220408B: Fermi GBM Final Localization
DATE:    22/04/08 13:59:04 GMT
FROM:    Elisabetta Bissaldi at INFN,Bari  <elisabetta.bissaldi@ba.infn.it>

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

At 07:28:04.65 UT on 8 Apr 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220408B (trigger 671095689.64512 / 220408311).

The on-ground calculated location, using the Fermi GBM trigger data, is RA =  94.8, Dec = -50.9 (J2000 degrees, equivalent to J2000 06h 19m, -50d 54'), with a statistical uncertainty of 2.2 degrees.

The angle from the Fermi LAT boresight is 30.3 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220408311/quicklook/glg_skymap_all_bn220408311.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220408311/quicklook/glg_healpix_all_bn220408311.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220408311/quicklook/glg_lc_medres34_bn220408311.gif


GRB_name: GRB220408A
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31855
SUBJECT: GRB 220408A: Swift/UVOT Detection
DATE:    22/04/08 15:34:23 GMT
FROM:    Samantha Oates at MSSL  <samantha.oates@alumni.ucl.ac.uk>

S. R. Oates (U.Birmingham) and R. Caputo (GSFC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 220408A
112 s after the BAT trigger (Caputo et al., GCN Circ. 31848).
A source consistent with the XRT position (Beardmore et al., GCN Circ. 31852)
is detected in the initial white UVOT exposure only.

Preliminary detections and 3-sigma upper limits 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

white (FC)         112          262          147        20.30 +/- 0.22
white              605         799          40        >21.4
v                  655         675          19        >19.3
b                  581         774          39        >20.7
u                  325         575         246        >20.2
w1                 704         724          19        >17.9
m2                 679         699          19        >17.4
w2                 631         650          19        >17.7

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.042 in the direction of the burst
(Schlegel et al. 1998).


GRB_name: GRB220408A
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31856
SUBJECT: GRB 220408A: Fermi GBM observation
DATE:    22/04/08 17:49:46 GMT
FROM:    Elisabetta Bissaldi at INFN,Bari  <elisabetta.bissaldi@ba.infn.it>

E. Bissaldi (Politecnico and INFN Bari) reports on behalf of the Fermi GBM 
Team:


"At 05:46:04.41 UT on 8 April 2022, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 220408A (trigger 671089569/ 220408240), which was also detected by the Swift/BAT (Caputo et al. 2022, GCN 31848). 
The Fermi GBM Final Real-time Localization (GCN 31847) is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 57 degrees. 

The GBM light curve consists of a multipeaked emission episode with a duration (T90) of about 20 s (50-300 keV).
The time-averaged spectrum from T0-0.8 s to T0+6.7 s is well fit by a power law function with an exponential high-energy cutoff. The power law index is -0.72 +/- 0.14 and the cutoff energy, parameterized as Epeak, is 48.8 +/- 2.3 keV.

The event fluence (10-1000 keV) in this time interval is (1.33 +/- 0.05)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+2.4 s in the 10-1000 keV band is 7.7 +/-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: GRB220408A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31857
SUBJECT: GRB 220408A: GIT optical upper limit
DATE:    22/04/08 19:05:42 GMT
FROM:    Harsh Kumar at Indian Inst of Tech,Bombay  <harshkosli13@gmail.com>

H. Kumar (IITB), V. Swain (IITB), R. Norbu (IAO), V. Bhalerao (IITB), G. C.
Anupama (IIA), S. Barway (IIA) report on behalf of the GIT team:

We observed GRB 220408A detected by Fermi-GBM (GCN #31847) and Swift-BAT
(R. Caputo et al., GCN #31848) with 0.7m GROWTH-India Telescope (GIT). We
obtained multiple 300-sec exposures in the r' filter and did not detect the
afterglow in our stacked images. The obtained upper limits follow as:
---------------------------------------------------------------------------------
 JD (mid) | T_mid-T0(hrs) | Exposure (sec) | Filter | Lim_mag (5-sigma) |
---------------------------------------------------------------------------------
2459678.21683 | 11.43 | 3000(stacked) | r' | > 21.94
---------------------------------------------------------------------------------

The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016)
and not corrected for Galactic extinction.

The GROWTH India Telescope (GIT) 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 operations of the telescope. Telescope technical
details are available at https://sites.google.com/view/growthindia/.


GRB_name: GRB220408B
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31858
SUBJECT: Fermi GRB 220408B: Global MASTER-Net observations report 
DATE:    22/04/08 19:30:22 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, D. Vlasenko, 
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(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. Gres, N.M. Budnev
(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),

A. Gabovich, V.Yurkov 
(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 220408B ( Fermi GBM team, GCN 31854) errorbox  38858 sec after notice time and 38887 sec after trigger time at 2022-04-08 18:16:12 UT, with upper limit up to  17.9 mag. The observations began at zenith distance = 33 deg. The sun  altitude  is -24.1 deg. 

The galactic latitude b = -25 deg., longitude l = 259 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1936782

We obtain a following upper limits.  

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

   38918 | 2022-04-08 18:16:12 |         MASTER-SAAO | (06h 12m 56.98s , -50d 05m 58.3s) |   C |    60 | 17.8 |        
   39007 | 2022-04-08 18:17:42 |         MASTER-SAAO | (06h 25m 30.38s , -50d 06m 55.8s) |   C |    60 | 17.9 |        
   39088 | 2022-04-08 18:19:03 |         MASTER-SAAO | (06h 04m 01.42s , -52d 01m 53.5s) |   C |    60 | 17.5 |        
   39180 | 2022-04-08 18:20:34 |         MASTER-SAAO | (06h 16m 56.43s , -52d 00m 18.7s) |   C |    60 | 17.4 |        
   39498 | 2022-04-08 18:25:52 |         MASTER-SAAO | (06h 33m 41.72s , -48d 11m 39.6s) |   C |    60 | 17.5 |        
   39589 | 2022-04-08 18:27:23 |         MASTER-SAAO | (06h 20m 15.24s , -53d 55m 36.6s) |   C |    60 | 17.6 |        
   39669 | 2022-04-08 18:28:43 |         MASTER-SAAO | (06h 33m 53.81s , -53d 55m 10.9s) |   C |    60 | 17.6 |        
   39997 | 2022-04-08 18:34:11 |         MASTER-SAAO | (06h 13m 03.64s , -50d 07m 10.9s) |   C |    60 | 17.4 |        
   40088 | 2022-04-08 18:35:42 |         MASTER-SAAO | (06h 25m 31.89s , -50d 05m 38.5s) |   C |    60 | 17.6 |        
   40172 | 2022-04-08 18:37:07 |         MASTER-SAAO | (06h 03m 58.08s , -52d 00m 16.1s) |   C |    60 | 17.5 |        
   40263 | 2022-04-08 18:38:37 |         MASTER-SAAO | (06h 16m 57.23s , -51d 59m 13.9s) |   C |    60 | 17.3 |        
   40354 | 2022-04-08 18:40:09 |         MASTER-SAAO | (06h 21m 52.59s , -48d 12m 07.9s) |   C |    60 | 17.5 |        
   40434 | 2022-04-08 18:41:28 |         MASTER-SAAO | (06h 33m 43.84s , -48d 13m 07.6s) |   C |    60 | 17.5 |        
   40537 | 2022-04-08 18:43:11 |         MASTER-SAAO | (06h 20m 24.77s , -53d 54m 58.6s) |   C |    60 | 17.3 |        
   40669 | 2022-04-08 18:45:23 |         MASTER-SAAO | (06h 33m 53.42s , -53d 53m 27.9s) |   C |    60 | 17.4 |        
   40840 | 2022-04-08 18:48:14 |         MASTER-SAAO | (06h 11m 00.85s , -48d 11m 45.8s) |   C |    60 | 17.5 |        
   40919 | 2022-04-08 18:49:33 |         MASTER-SAAO | (06h 13m 02.11s , -50d 04m 46.1s) |   C |    60 | 17.4 |        
   41011 | 2022-04-08 18:51:05 |         MASTER-SAAO | (06h 25m 34.52s , -50d 05m 46.3s) |   C |    60 | 17.7 |        
   41106 | 2022-04-08 18:52:40 |         MASTER-SAAO | (06h 04m 01.19s , -52d 00m 39.5s) |   C |    60 | 17.1 |        
   41195 | 2022-04-08 18:54:09 |         MASTER-SAAO | (06h 17m 05.09s , -52d 00m 21.5s) |   C |    60 | 17.2 |        
   41291 | 2022-04-08 18:55:45 |         MASTER-SAAO | (06h 21m 50.81s , -48d 10m 39.6s) |   C |    60 | 17.8 |        
   41370 | 2022-04-08 18:57:05 |         MASTER-SAAO | (06h 33m 49.29s , -48d 12m 25.5s) |   C |    60 | 17.3 |        
   41474 | 2022-04-08 18:58:48 |         MASTER-SAAO | (06h 20m 25.74s , -53d 52m 38.1s) |   C |    60 | 17.2 |        
   41565 | 2022-04-08 19:00:19 |         MASTER-SAAO | (06h 33m 52.54s , -53d 53m 31.3s) |   C |    60 | 17.6 |        
   41738 | 2022-04-08 19:03:12 |         MASTER-SAAO | (06h 36m 42.34s , -50d 06m 22.0s) |   C |    60 | 17.6 |        
   41817 | 2022-04-08 19:04:32 |         MASTER-SAAO | (06h 11m 06.65s , -48d 11m 50.7s) |   C |    60 | 17.7 |        
   42081 | 2022-04-08 19:08:55 |         MASTER-SAAO | (06h 01m 51.27s , -50d 04m 52.3s) |   C |    60 | 17.6 |        
   42252 | 2022-04-08 19:11:46 |         MASTER-SAAO | (06h 08m 09.12s , -53d 53m 57.1s) |   C |    60 | 17.7 |        
   42785 | 2022-04-08 19:20:39 |         MASTER-SAAO | (06h 36m 45.22s , -50d 05m 41.5s) |   C |    60 | 17.6 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220408A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31859
SUBJECT: GRB 220408A: BOOTES-5/JGT optical afterglow detection
DATE:    22/04/08 23:17:25 GMT
FROM:    Youdong HU at IAA-CSIC  <huyoudong072@hotmail.com>

Y.-D. Hu, E. Fernandez-Garcia, T.-R. Sun, A. J. Castro-Tirado, R. Sanchez-Ramirez and M.D. Caballero-Garcia (IAA-CSIC), D. Hiriart and W. H. Lee (UNAM), C. J. Perez del Pulgar and I. Carrasco (UMA), I. H. Park (SKKU) on behalf of a larger collaboration, report:

Following the detection of GRB 220408A by both Swift (Caputo et al. GCNC 31848) and Fermi (Fermi GBM team, GCNC 31847), the 60cm BOOTES-5/JGT robotic telescope at Observatorio Astronomico Nacional in San Pedro Martir (Mexico) automatically responded to the burst on Apr 8 at 06:14 UT (i.e. ~ 28 min after trigger). In the co-added image (5 frames x 60 s exposure, clear filter), the optical afterglow is weakly detected with R = 21.1 +/- 0.3 mag at the position reported by UVOT (Caputo et al. GCNC 31848) and within the XRT error box (Beardmore et al. GCNC 31852). This is consistent with other optical detections previously reported by UVOT (Caputo et al. GCNC 31848, Oates et al. GCNC 31855) and KAIT (Zheng et al. GCNC 31850) and the upper limits provided by MASTER (Lipunov et al. GCNC 31849), Xinglong-2.16m (Jiang et al. GCNC 21853) and GIT (Kumar et al. GCNC 31857). Further observations are ongoing.

We thank the staff at San Pedro Martir Observatory for their excellent support.


GRB_name: GRB220403C
Detection_method: Swift Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31860
SUBJECT: GRB 220403C: Swift ToO observations
DATE:    22/04/09 04:25:33 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

P. A. Evans (U. Leicester) reports on behalf of the Swift team:

Swift has initiated a ToO observation of the Fermi/GBM GRB 220403C. 
Automated analysis of the XRT data will be presented online at
https://www.swift.ac.uk/ToO_GRBs/00021484

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 Fermi/GBM 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: GRB220408A
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31861
SUBJECT: GRB 220408A: Swift-XRT refined Analysis
DATE:    22/04/09 08:44:36 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

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

We have analysed 7.5 ks of XRT data for GRB 220408A (Caputo et al. GCN
Circ. 31848), from 93 s to 63.6 ks after the  BAT trigger. The data
comprise 10 s in Windowed Timing (WT) mode (taken while Swift was
slewing), with the remainder in Photon Counting (PC) mode. The enhanced
XRT position for this burst was given by Beardmore et al. (GCN Circ.
31852).

The light curve can be modelled with an initial power-law decay with an
index of alpha=0.46 (+0.16, -0.17), followed by a break at T+2306 s to
an alpha of 1.37 (+0.16, -0.15).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.94 (+0.23, -0.22). The
best-fitting absorption column is  1.8 (+0.8, -0.7) x 10^21 cm^-2, in
excess of the Galactic value of 2.0 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 3.6 x 10^-11 (4.8 x 10^-11) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:      1.8 (+0.8, -0.7) x 10^21 cm^-2
Galactic foreground: 2.0 x 10^20 cm^-2
Excess significance: 3.8 sigma
Photon index:      1.94 (+0.23, -0.22)

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01101675.

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


GRB_name: GRB220408A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31862
SUBJECT: GRB 220408A: LCO Optical Afterglow Detection
DATE:    22/04/09 10:15:46 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (College of Marin) report on behalf of a larger collaboration:

We observed Swift (Caputo et al. GCN 31848) and Fermi (Fermi GBM team, GCN 31847) GRB220408A with the LCO 1-m Sinistro instrument at the McDonald Observatory, Texas, USA site, on April 9, from 06:30 to 06:57 UT (corresponding to 0.63 to 1.18 hours from the GRB trigger time) with the Bessel R and I filters.

We performed a series of 3x300s exposures in I and R bands. We detect an optical counterpart within the XRT enhanced error region (Beardmore et al., GCN 31852) in both bands, consistent with other optical detections  (Caputo et al. GCNC 31848, Zheng et al. GCNC 31850, Oates et al. GCNC 31855). The following magnitudes are calculated using the USNO-B.1 catalog as reference:

R=21.66+/-0.17
I=19.63+/-0.11

These magnitudes are not corrected for galactic extinction.

R.S. is funded by NSF AST grant #1831682


GRB_name: GRB220408B
Detection_method: AstroSat CZTI
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31863
SUBJECT: GRB 220408B: AstroSat CZTI detection
DATE:    22/04/09 11:38:11 GMT
FROM:    Gaurav Waratkar at IIT,Bombay  <gauravwaratkar@iitb.ac.in>

R. Gopalakrishnan (IUCAA), V. Prasad (IUCAA), G. Waratkar (IITB), A.
Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (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 detection of a long GRB 220408B which was
also detected by Fermi-GBM (GCN 31854).

The source was clearly detected in the 20-200 keV energy range. The
light curve showed multiple peaks of emission with the strongest peak at
2022-04-08 07:28:08.50 UT. The measured peak count rate associated with
the burst is 1181 (+79, -36) counts/s above the background in the
combined data of all four quadrants, with a total of 12408 (+531, -419)
counts. The local mean background count rate was 516 (+2, -4) counts/s.
Using cumulative rates, we measure a T90 of  25 (+3, -1) s.

It 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 2022-04-08 07:28:08.19 UT. The
measured peak count rate is 1215 (+93, -70) counts/s  above the
background in the combined Veto data of four quadrants, with a total of
10873 (+743, -663) counts. The local mean background count rate was 1882
(+4, -5) counts/s. We measure a T90 of 24 (+2, -6) s from the cumulative
Veto light curve.

CZTI GRB detections are reported regularly on the payload site at
http://astrosat.iucaa.in/czti/?q=grb [1]. CZTI is built by a TIFR-led
consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC,
and PRL. The Indian Space Research Organisation funded, managed, and
facilitated the project.
 

Links:
------
[1] http://astrosat.iucaa.in/czti/?q=grb


GRB_name: GRB220408A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31864
SUBJECT: GRB 220408A: NOT optical observations and archival detection
DATE:    22/04/09 14:01:01 GMT
FROM:    Zipei Zhu at NAOC  <zpzhu@nao.cas.cn>

Z. Zhu (NAO/CAS, HUST), D. Xu, S.Y. Fu (NAOC/CAS), D. B. Malesani (Radboud Univ and DAWN/NBI), A. de Ugarte Postigo (Obs. Cote d'Azur), A. J. Levan (Radboud univ.), M. Aron (NOT), report on behalf of a larger collaboration:

We observed the field of GRB 220408A detected by Swift (Caputo et al., GCN 31848) and Fermi (Fermi GBM team, GCN 31847) using the Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. Observations were carried out starting at 03:53:08 UT on 2022-04-09 (i.e., 0.92 day since the BAT trigger), and 6x300 s frames in the SDSS r-band were obtained.

The previously reported optical counterpart (e.g., Caputo et al., GCN 31848; Zheng & Filippenko, GCN 31850; Oates et al., GCN 31855; Hu et al., GCN 31859; Strausbaugh & Cucchiara, GCN 31862) is detected in our stacked image with r = 24.1 +/- 0.1 AB, calibrated against nearby stars from the Pan-STARRS catalog.

We note that this field was covered by an image taken in 2007 with CFHT. Consistent with the UVOT coordinates, a faint source is visible with r = 24.5 +/- 0.2 (AB). While the S/N is not large, and we cannot conclusively determine whether this object is extended, it is a viable host galaxy candidate, suggesting a distance to the GRB much larger than M51.

We encourage spectroscopic observations of this Northern target to conclusively measure.


GRB_name: GRB220408A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31865
SUBJECT: GRB 220408A: redshift lower limit estimating
DATE:    22/04/09 15:51:10 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 analysed GRB 220408A detected by Fermi (Fermi GBM team, GCN 31847; 
Bissaldi et al., GCN 31856), by Swift (GCN Caputo et al., GCN 31848). 
Using publicly available data of GBM/Fermi we estimate the duration 
T_90 = 32.3 +/- 2.5 s in   (7 - 150) keV energy band. We performed 
spectral analysis in a time interval of (-1, 22) s since GBM trigger, 
the best fit is obtained for Band model with following parameters: E_p = 
36.5 +/- 5.0 keV, alpha = -0.50 +/- 0.35, beta = -2.5 +/- 0.2. The 
fluence of F = (2.0 +/- 0.2)E-6 erg/cm**2 is obtained in 10 - 1000 keV 
energy band. Using T_90,i - EH diagram [1,2] we can classify the burst 
as type II (long)  and find the minimal possible redshift value of z = 
0.03, which is excluding possible association with M51 galaxy and 
confirming larger distance of GRB 220408A  (Zhu et., GCN 31864).

The T_90,i - EH diagram can be found in 
http://grb.rssi.ru/GRB220408A/GRB220408A_EHD.png

[1] - Minaev et al., MNRAS, 492, 1919, 2020
[2] - Minaev et al., Astronomy Letters, 46, 9, 573, 2020


GRB_name: GRB220403C
Detection_method: Swift-XRT Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31866
SUBJECT: GRB 220403C: Swift-XRT observations
DATE:    22/04/09 18:56:40 GMT
FROM:    Phil Evans at U of Leicester  <pae9@leicester.ac.uk>

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

Swift-XRT has performed follow-up observations of GRB 220403C, detected
outside the BAT coded FOV by GUANO NITRATES (Aaron Tohuvavohu et al.
GCN Circ. 31824), as well as by Fermi-GBM, INTEGRAL, CALET and
ISS-ASIM, collecting 3.2 ks of Photon Counting (PC) mode data between
T0+497.7 ks and T0+528.5 ks. 

Six uncatalogued X-ray sources have been detected, however none of them
is above the RASS limit or shows definitive signs of fading. Therefore,
at the present time we cannot identify which, if any, is the afterglow.
Details of these sources are given below:

Source 1:
  RA (J2000):  19.7120  =  01:18:50.87
  Dec (J2000): -56.4530  =  -56:27:10.8
  Error: 11.4 arcsec (radius, 90% conf.)
  Count-rate: (3.7 [+3.1, -2.2])e-3 ct s^-1   
  Distance: 515 arcsec from ASIM position.

Source 2:
  RA (J2000):  19.6293  =  01:18:31.04
  Dec (J2000): -56.3726  =  -56:22:21.5
  Error: 8.4 arcsec (radius, 90% conf.)
  Count-rate: (3.8 [+3.0, -2.2])e-3 ct s^-1   
  Distance: 530 arcsec from ASIM position.

Source 3:
  RA (J2000):  19.7466  =  01:18:59.17
  Dec (J2000): -56.4578  =  -56:27:28.0
  Error: 9.1 arcsec (radius, 90% conf.)
  Count-rate: (6.2 [+3.7, -2.8])e-3 ct s^-1   
  Distance: 484 arcsec from ASIM position.

Source 4:
  RA (J2000):  19.7142  =  01:18:51.41
  Dec (J2000): -56.2603  =  -56:15:37.1
  Error: 6.7 arcsec (radius, 90% conf.)
  Count-rate: (4.3 [+1.7, -1.3])e-3 ct s^-1   
  Distance: 479 arcsec from ASIM position.
  Flux: (2.90 [+1.13, -0.91])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)


Source 5:
  RA (J2000):  19.7189  =  01:18:52.53
  Dec (J2000): -56.2878  =  -56:17:16.2
  Error: 6.8 arcsec (radius, 90% conf.)
  Count-rate: (1.17 [+1.01, -0.72])e-3 ct s^-1  
  Distance: 411 arcsec from ASIM position.

Source 6:
  RA (J2000):  19.9526  =  01:19:48.63
  Dec (J2000): -56.2605  =  -56:15:37.7
  Error: 6.8 arcsec (radius, 90% conf.)
  Count-rate: (2.13 [+1.25, -0.92])e-3 ct s^-1  
  Distance: 344 arcsec from ASIM position.

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/00021484.

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


GRB_name: GRB220408A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31867
SUBJECT: GRB 220408A: LOAO, DOAO, and, SAO optical upper limit
DATE:    22/04/10 03:03:22 GMT
FROM:    Gregory SungHak Paek at SNU  <shpaek@astro.snu.ac.kr>

Gregory S.H. Paek (SNU ARC/SNU), Myungshin Im (SNU ARC/SNU), Taewoo Kim
(DOAO), Jinguk Seo (SAO), Yuji Urata (NCU), Hyun-Il Sung (KASI) on behalf
of a larger collaboration

 We searched for the optical counterpart of GRB 220408A possibly associated
with M51 (Caputo et al., and GCN #31848; Fermi/GBM detection, GCN #31847)
with the 1-m class telescopes in Lemonsan Optical Astronomy Observatory
(LOAO), Deokheung Optical Astronomy Observatory (DOAO), and Seoul National
University Astronomy Observatory (SAO), facilities of the GW EM-Counterpart
Korean Observatory (GECKO).

 We observed the center of UVOT localization (RA, Dec = 202.41548,
+47.06931) +2.94 hours after the report, but could not find any detection.
We calibrated flux with the PANSTARRS catalog and used an AB magnitude
system. Depth means 5 sigma upper limit for a point source detection. The
magnitudes are not corrected for galactic extinction.

------------------- ----------- ---------- ----=------ ------ -----------
---------- -----
DATE-OBS[UTC]       JD          t-t0[days] t-t0[hours] FILTER Observatory
EXPTIME[s] DEPTH
------------------- ----------- ---------- ----=------ ------ -----------
---------- -----
2022-04-08T11:29:38 2459677.979 0.239      5.7         R      LOAO
 180s*12    21.42
2022-04-08T15:44:59 2459678.156 0.416      10.0        V      SAO
 180s*21    19.75
2022-04-08T15:57:20 2459678.165 0.424      10.2        R      DOAO
 300s*37    21.90
2022-04-08T16:58:50 2459678.208 0.467      11.2        R      SAO
180s*21    19.77

Gravitational-wave EM Counterpart Korean Observatory (GECKO) is a network
of 10+ 0.5m to 1m class telescopes over the world.


GRB_name: GRB220408A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31868
SUBJECT: GRB 220408A: 1.3m DFOT Optical upper limit
DATE:    22/04/10 12:07:00 GMT
FROM:    Amit Kumar at ARIES, India  <amitkundu515@gmail.com>

 Amit Kumar, Rahul Gupta, Amit K. Ror, Nikita Rawat, Dimple, Ankur Ghosh,
Amar Aryan, Brajesh Kumar, Shashi B. Pandey and Kuntal Misra (ARIES)
report:

We observed the field of the Swift-BAT (Caputo et al., GCN 31848) and
Fermi-GBM (GBM Team, GCN 31847) detected GRB 220408A with the 1.3m
Devasthal Fast Optical Telescope (DFOT) located at Devasthal observatory of
Aryabhatta Research Institute of Observational Sciences (ARIES), India. We
started the observations on 2022-04-08 at 16:27:57 UT, i.e., ~10.698 hours
after the GBM trigger. We have observed 300s*23 frames in each Bessel R and
I filters. We stacked the images after the pre-processing and alignment. We
did not detect the optical afterglow at the Swift-XRT position (Beardmore
et al., GCN 31852) in our stacked images; see also Caputo et al., GCN
31848; Zheng & Filippenko, GCN 31850; Jiang et al., GCN 31853; Oates &
Caputo, GCN 31855; Kumar et al., GCN 31857; Hu et al., GCN 31859;
Strausbaugh et al., GCN 31862; Zhu et al., GCN 31864; and Gregory et al.,
GCN 31867.


We obtain the following 3-sigma upper limits in the stacked images.

Date Start_UT T_start-T0 (hour) Filter Exp time(s) Limiting magnitude
====================================================
2022-04-08 16:27:57 ~10.698 R 300s*23 >22.5
2022-04-08 18:29:56 ~12.731 I  300s*23 >22.1


The magnitudes are not corrected for the Galactic extinction in the burst
direction. Photometric calibration is performed using the standard stars
from the USNO-B1.0 catalogue.

During our observations, the moon phase and its distance were ~45% and
~55-66 degrees, respectively, which affected our deeper limits
significantly; see Kumar et al. 2021, JAA, arXiv:2111.13018 (
https://ui.adsabs.harvard.edu/abs/2000A%26A...363..705M/abstract) for the
sky brightness of the Devasthal site w.r.t. the moon phase and distance.

Assuming a typical temporal flux decay index of the early afterglows
(alpha~0.7), the extrapolated brightness at the epoch of our observation is
consistent with the quoted non-detection. Deeper observations using the
larger facilities will be useful to establish the fast decaying nature of
the burst and to investigate for this burst to happen in any
distant/background galaxy rather than Whirlpool Galaxy (M51a).

This message may be cited.


GRB_name: GRB220403B
Detection_method: Fermi GBM Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31869
SUBJECT: GRB 220403B: 1.3m DFOT Optical upper limit
DATE:    22/04/10 12:39:32 GMT
FROM:    Rahul Gupta at ARIES, India  <rahulbhu.c157@gmail.com>

Amit Kumar Ror, Rahul Gupta, Amit Kumar, Dimple, Ankur Ghosh, Amar Aryan,
Brajesh Kumar, S. B. Pandey, and Kuntal Misra (ARIES) report:


We observed the Swift-BAT and Fermi-GBM detected GRB 220403B (Klingler et
al., GCN 31820; Hamburg et al., GCN 31829) with 1.3m Devasthal Fast Optical
Telescope (DFOT) located at Devasthal observatory of Aryabhatta Research
Institute of Observational Sciences (ARIES), India. The observations were
started on 2022-04-04 at ~ 17:32 UT, i.e., ~ 20.82 hours after the BAT
trigger. We have taken multiple frames having an exposure time of 300 sec
in the R filter. We stacked the images after the alignment. We did not
detect the optical afterglow (Klingler et al., GCN 31820; Jelinek et al.,
GCN 31821; Zhu et al., GCN 31823; Lipunov et al., GCN 31825; Rossi GCN
31826; Pankov et al., GCN 31837; and Hu et al., GCN 31841) in our stacked
image.

We obtain the following 3-sigma upper limit in the stacked image.


Date Start_UT T_start-T0 (hours) Filter  Exp time (sec)  Limiting magnitude

=============================================================
2022-04-04 17:32:01    ~20.82                 R        300 sec*24
 > 21.6


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: GRB220408A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31870
SUBJECT: GRB 220408A: RATIR Optical and NIR Observations 
DATE:    22/04/10 17:38:55 GMT
FROM:    Alan M Watson at UNAM  <alan@astro.unam.mx>

Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Eleonora Troja (GSFC), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Enrico Ramirez-Ruiz (UCSC), JesÃºs GonzÃ¡lez (UNAM), Carlos RomÃ¡n-ZÃºÃ±iga (UNAM), Harvey Moseley (GSFC), Rosa L. Becerra (UNAM), Simone Dichiara (UMD), and OcÃ©lotl LÃ³pez (UNAM) report:

We observed the field of GRB 220408A (Caputo et al., GCN Circ. 31848) with the Reionization and Transients Infrared Camera (RATIR) on the 1.5m Harold Johnson Telescope at the Observatorio AstronÃ³mico Nacional on Sierra San Pedro MÃ¡rtir from 2022/04 9.13 to 2022/04 9.49 UTC (20.98 to 29.45 hours after the BAT trigger), obtaining a total of 3.27 hours exposure in the r and i bands and 2.10 hours exposure in the Z, Y, J, and H bands.

For a source within the Swift-XRT error circle, in comparison with the USNO-B1 and 2MASS catalogs, we obtain the following weak detection and 3-sigma upper limits:

  r > 23.76
  i > 23.45
  Z > 21.36
  Y > 22.04
  J > 21.79
  H = 21.27 +/- 0.23

These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. We note that while we have a formal detection in H, the large errors call it into doubt.

Our limit in r is consistent with the fainter and slightly earlier detection at r = 24.1 reported by Zhu et al. (GCN Circ. 31864).

We thank the staff of the Observatorio AstronÃ³mico Nacional in San Pedro MÃ¡rtir.


GRB_name: GRB220411A
Detection_method: Fermi GBM final loc
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31871
SUBJECT: GRB 220411A: Fermi GBM Final Real-time Localization
DATE:    22/04/11 07:29:20 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 07:20:00 UT on 11 Apr 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220411A (trigger 671354405.530438 / 220411306).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 178.2, Dec = 25.6 (J2000 degrees, equivalent to J2000 11h 52m, 25d 36'), with a statistical uncertainty of 1.7 degrees.

The angle from the Fermi LAT boresight is 6.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220411306/quicklook/glg_skymap_all_bn220411306.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220411306/quicklook/glg_healpix_all_bn220411306.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn220411306/quicklook/glg_lc_medres34_bn220411306.gif


GRB_name: GRB220411A
Detection_method: Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31872
SUBJECT: GRB 220411A: BALROG localization (Fermi Trigger  671354405/ GRB 220411306)
DATE:    22/04/11 08:12:32 GMT
FROM:    Jochen Greiner at MPE,Garching  <jcg@mpe.mpg.de>

F. Kunzweiler, B. Biltzinger, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:

The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
671354405 at 07:20:00 on 11 April 2022 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) = 176.5+/-1.5 deg
Decl.(2000.0) = 24.0+/-2.6 deg
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB220411306/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB220411306/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB220411306/json

                        


GRB_name: GRB220411A
Detection_method: Fermi GBM Other
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31873
SUBJECT: Fermi GRB 220411A: Global MASTER-Net observations report 
DATE:    22/04/11 08:30:29 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, D. Vlasenko, 
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(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. Gres, N.M. Budnev
(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),

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


MASTER-OAGH robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) started inspect of the Fermi GRB 220411A ( Fermi GBM team, GCN 31871) errorbox  32 sec after notice time and 62 sec after trigger time at 2022-04-11 07:21:03 UT, with upper limit up to  17.5 mag. The observations began at zenith distance = 20 deg. The sun  altitude  is -50.8 deg. 

The galactic latitude b = 77 deg., longitude l = 218 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1939159

We obtain a following upper limits.  

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

      68 | 2022-04-11 07:21:03 |         MASTER-OAGH | (11h 52m 52.63s , +26d 05m 41.6s) |  P- |    10 | 14.4 |        
     104 | 2022-04-11 07:21:34 |         MASTER-OAGH | (11h 52m 48.93s , +26d 07m 11.8s) |  P- |    20 | 15.9 |        
     150 | 2022-04-11 07:22:15 |         MASTER-OAGH | (11h 53m 18.01s , +25d 38m 16.8s) |   C |    30 | 12.1 |        
     150 | 2022-04-11 07:22:15 |         MASTER-OAGH | (11h 52m 48.76s , +26d 05m 30.2s) |  P- |    30 | 16.8 |        
     210 | 2022-04-11 07:23:10 |         MASTER-OAGH | (11h 52m 52.09s , +26d 07m 01.4s) |  P- |    40 | 16.3 |        
     298 | 2022-04-11 07:24:33 |         MASTER-OAGH | (11h 52m 45.16s , +26d 06m 06.2s) |  P- |    50 | 16.3 |        
     298 | 2022-04-11 07:24:33 |         MASTER-OAGH | (11h 53m 14.19s , +25d 38m 45.3s) |   C |    50 | 12.5 |        
     390 | 2022-04-11 07:25:55 |         MASTER-OAGH | (11h 53m 14.35s , +25d 39m 45.2s) |   C |    70 | 12.5 |        
     390 | 2022-04-11 07:25:55 |         MASTER-OAGH | (11h 52m 45.14s , +26d 07m 03.3s) |  P- |    70 | 16.6 |        
     491 | 2022-04-11 07:27:26 |         MASTER-OAGH | (11h 52m 51.45s , +26d 06m 02.5s) |  P- |    90 | 15.3 |        
     613 | 2022-04-11 07:29:18 |         MASTER-OAGH | (11h 53m 08.87s , +25d 38m 00.0s) |   C |   110 | 12.4 |        
     613 | 2022-04-11 07:29:18 |         MASTER-OAGH | (11h 52m 45.44s , +26d 05m 00.2s) |  P- |   110 | 16.6 |        
     761 | 2022-04-11 07:31:31 |         MASTER-OAGH | (11h 53m 16.06s , +25d 37m 53.4s) |   C |   140 | 12.8 |        
     761 | 2022-04-11 07:31:31 |         MASTER-OAGH | (11h 52m 52.62s , +26d 05m 00.5s) |  P- |   140 | 16.8 |        
     944 | 2022-04-11 07:34:19 |         MASTER-OAGH | (11h 52m 49.29s , +26d 06m 36.6s) |  P- |   170 | 17.3 |        
     944 | 2022-04-11 07:34:19 |         MASTER-OAGH | (11h 53m 18.70s , +25d 39m 19.9s) |   C |   170 | 12.3 |        
    1141 | 2022-04-11 07:37:31 |         MASTER-OAGH | (11h 53m 18.99s , +25d 37m 48.3s) |   C |   180 | 12.5 |        
    1141 | 2022-04-11 07:37:31 |         MASTER-OAGH | (11h 52m 49.51s , +26d 05m 09.8s) |  P- |   180 | 17.0 |        
    1376 | 2022-04-11 07:41:26 |         MASTER-OAGH | (11h 53m 22.33s , +25d 39m 17.1s) |   C |   180 | 12.9 |        
    1376 | 2022-04-11 07:41:26 |         MASTER-OAGH | (11h 52m 52.96s , +26d 06m 39.9s) |  P- |   180 | 17.1 |        
    1616 | 2022-04-11 07:45:26 |         MASTER-OAGH | (11h 52m 47.04s , +26d 06m 00.2s) |  P- |   180 | 17.2 |        
    1758 | 2022-04-11 07:48:48 |         MASTER-OAGH | (11h 44m 46.14s , +26d 20m 59.3s) |   C |    60 | 17.1 |        
    2083 | 2022-04-11 07:54:13 |         MASTER-OAGH | (11h 54m 00.64s , +25d 53m 10.6s) |   C |    60 | 12.4 |        
    2083 | 2022-04-11 07:54:13 |         MASTER-OAGH | (11h 53m 35.38s , +26d 20m 18.2s) |   C |    60 | 17.1 |        
    2165 | 2022-04-11 07:55:35 |         MASTER-OAGH | (11h 50m 30.92s , +24d 27m 07.4s) |   C |    60 | 16.0 |        
    2246 | 2022-04-11 07:56:56 |         MASTER-OAGH | (11h 59m 16.98s , +24d 28m 08.3s) |   C |    60 | 16.3 |        
    2429 | 2022-04-11 07:59:59 |         MASTER-OAGH | (11h 48m 33.06s , +28d 14m 02.1s) |   C |    60 | 17.0 |        
    2515 | 2022-04-11 08:01:25 |         MASTER-OAGH | (11h 56m 38.11s , +28d 13m 55.7s) |   C |    60 | 17.1 |        
    2767 | 2022-04-11 08:05:37 |         MASTER-OAGH | (11h 44m 39.76s , +26d 21m 01.6s) |   C |    60 | 16.4 |        
    2848 | 2022-04-11 08:06:58 |         MASTER-OAGH | (12h 01m 40.16s , +26d 21m 01.6s) |   C |    60 | 17.1 |        
    3011 | 2022-04-11 08:09:41 |         MASTER-OAGH | (11h 53m 39.58s , +26d 20m 06.2s) |   C |    60 | 16.8 |        
    3097 | 2022-04-11 08:11:07 |         MASTER-OAGH | (11h 50m 34.31s , +24d 27m 48.4s) |   C |    60 | 16.6 |        
    3178 | 2022-04-11 08:12:28 |         MASTER-OAGH | (11h 59m 19.92s , +24d 26m 29.8s) |   C |    60 | 17.5 |        
    3272 | 2022-04-11 08:14:02 |         MASTER-OAGH | (11h 39m 57.05s , +27d 48m 51.2s) |   C |    60 | 12.7 |        
    3376 | 2022-04-11 08:15:46 |         MASTER-OAGH | (11h 48m 58.26s , +27d 47m 33.3s) |   C |    60 | 12.5 |        
    3376 | 2022-04-11 08:15:46 |         MASTER-OAGH | (11h 48m 25.73s , +28d 14m 53.5s) |   C |    60 | 17.0 |        
    3476 | 2022-04-11 08:17:26 |         MASTER-OAGH | (11h 56m 34.57s , +28d 15m 55.0s) |   C |    60 | 16.5 |        
    3666 | 2022-04-11 08:20:36 |         MASTER-OAGH | (11h 44m 41.17s , +26d 20m 00.7s) |   C |    60 | 16.5 |        
    3980 | 2022-04-11 08:25:50 |         MASTER-OAGH | (11h 49m 16.26s , +22d 32m 35.4s) |   C |    60 | 16.6 |        
Filter C is a clear (unfiltred) band. 


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


GRB_name: GRB220408A
Detection_method: Swift-BAT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31874
SUBJECT: GRB 220408A: Swift-BAT refined analysis
DATE:    22/04/11 12:34:25 GMT
FROM:    Takanori Sakamoto at AGU  <tsakamoto@phys.aoyama.ac.jp>

D. M. Palmer (LANL), S. D. Barthelmy (GSFC), R. Caputo (GSFC),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa),
C. B. Markwardt (GSFC), T. Parsotan (GSFC/UMBC),
T. Sakamoto (AGU), M. Stamatikos (OSU)
(i.e. the Swift-BAT team):
  
Using the data set from T-119 to T+183 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 220408A (trigger #1101675)
(Caputo, et al., GCN Circ. 31848).  The BAT ground-calculated position is
RA, Dec = 202.399, 47.065 deg which is
    RA(J2000)  =  13h 29m 35.7s
    Dec(J2000) = +47d 03' 55.4"
with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 34%.
  
The mask-weighted light curve shows a multi-peaked structure that
starts at T-2 s and peaks at T+3 s.  There is a weak emission which
peaks at T+17 s.  T90 (15-350 keV) is 17.25 +- 1.10 sec
(estimated error including systematics).
  
The time-averaged spectrum from T-0.55 to T+18.26 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 1.19 +- 0.57,
and Epeak of 35.3 +- 8.8 keV (chi squared 62.40 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 1.2 +- 0.1 x 10^-6 erg/cm2
and the 1-sec peak flux measured from T+2.48 sec in the 15-150 keV band is
4.9 +- 0.4 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 2.14 +- 0.13 (chi squared 72.77 for 57 d.o.f.).  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/1101675/BA/


GRB_name: GRB220408A
Detection_method: Optical
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31875
SUBJECT: GRB 220408A: Lowell Discovery Telescope Optical Observations
DATE:    22/04/11 13:55:36 GMT
FROM:    Brendan O'Connor at UMD  <oconnorb@umd.edu>

B. O'Connor (UMD, GWU), S.B. Cenko (UMD,NASA-GSFC), E. Troja (UTV),
S. Dichiara (PSU), A. Kutyrev (UMD,NASA-GSFC), S. Veilleux (UMD)

We observed GRB 220408A with the Large Monolithic Imager (LMI) on the 4.3m
Lowell Discovery Telescope (LDT). Observations began on April 9, 2022
at 06:25:23 UT in r-band (~1.03 d after the GRB). At the location of the
optical counterpart (Caputo et al., GCN 31848), we marginally detect a
source with magnitude r~24.5 +/- 0.3 AB mag. This is likely dominated by
the contribution from the host galaxy (Zhu et al., GCN 31864), and is
consistent with fading of the earlier detection by Zhu et al. (GCN 31864).

Magnitudes are calibrated against the PS1 catalog and are not corrected
for Galactic extinction.

We thank the staff of the Lowell Discovery Telescope for assistance
with these observations.


GRB_name: GRB220403B
Detection_method: Swift-UVOT Det
Circular_text:
TITLE:   GCN CIRCULAR
NUMBER:  31876
SUBJECT: GRB 220403B: Swift/UVOT Detection
DATE:    22/04/11 17:51:22 GMT
FROM:    Noel Klingler at NASA-GSFC / UMBC  <njk5441@psu.edu>

N. J. Klingler (NASA-GSFC/UMBC/CRESST II) reports on behalf of the
Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 220403B
105 s after the BAT trigger (Klingler et al., GCN Circ. 31820).
A source consistent with the XRT position
is detected in the initial UVOT exposures.

The UVOT position is:
    RA  (J2000) =  12:45:53.46 = 191.47274 (deg.)
    Dec (J2000) = +89:11:06.5  =  89.18515 (deg.)
with an estimated uncertainty of 0.52 arc sec. (radius, 90% confidence).

Preliminary detections and 3-sigma upper limits 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

white              105          255          147         19.86 +/- 0.12
v                  647         1074           58        >18.6
b                  573          766           39        >19.3
u                  318          741          265         19.93 +/- 0.22
w1                 697          716           19        >18.9
w2                 797         1049           39        >19.9

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.208 in the direction of the burst
(Schlegel et al. 1998).


