GRB230512A

This page lists all entries on GRB230512A in GRBweb

Summary Fermi GBM IPN GCN 33778 GCN 33779 GCN 33780 GCN 33781 GCN 33784 GCN 33785 GCN 33786 GCN 33789 GCN 33795 GCN 33796 GCN 33797 GCN 33798 GCN 33799 GCN 33800 GCN 33802 GCN 33808

Summary table
Variable Value Source
GRB_name_Fermi GRB230512269
T0 6:27:45 UTC GCN_circulars,Fermi GBM Det
ra 295.4000° IPN
decl 38.4000° IPN
pos_error 3.00e-01° IPN
T90 2.624 s Fermi_GBM
T90_error 0.091 s Fermi_GBM
T90_start 6:27:45.413 UTC Fermi_GBM
fluence 1.10e-05 erg/cm² Fermi_GBM
fluence_error 1.44e-08 erg/cm² Fermi_GBM
T100 3.037 s
GBM_located False
mjd 60076.269270833334 GCN_circulars,Fermi GBM Det
Fermi GBM table
GRB_name_Fermi GRB230512269
trigger_name bn230512269
ra 295.4000°
decl 38.4000°
pos_error 2.55e+00°
datum 2023-05-12
t_trigger 6:27:45.413 UTC
T90 2.624 s
T90_error 0.091 s
T90_start 6:27:45.413 UTC
fluence 1.10e-05 erg/cm²
fluence_error 1.44e-08 erg/cm²
flux_1024 1.82e+01 erg/cm²/s
flux_1024_error 2.85e-01 erg/cm²/s
flux_1024_time 1.47e+00 erg/cm²/s
flux_64 2.76e+01 erg/cm²/s
flux_64_error 1.38e+00 erg/cm²/s
IPN table
GRB_name GRB230512A
ra 295.4000°
decl 38.4000°
pos_error 3.00e-01°
GCN 33778 table
GRB_name GRB230512A
GCN_number 33778
Detection_method Fermi GBM Other
ra 277.6200°
decl 53.8700°
Circular_text TITLE: GCN CIRCULAR NUMBER: 33778 SUBJECT: GRB 230512A: Fermi GBM Final Localization DATE: 23/05/12 11:59:08 GMT FROM: R. Hamburg at CNRS/IJCLab The Fermi GBM team reports the detection of a Short Bright GRB. At 06:27:45 UT on 12 May 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230512A (trigger 705565670/230512269). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 277.62, Dec = +53.87 (J2000 degrees, equivalent to J2000 18h 30m, +53d 53'), with a statistical uncertainty of 1 degree. The angle from the Fermi LAT boresight is 26 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230512269/quicklook/glg_skymap_all_bn230512269.png The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230512269/quicklook/glg_healpix_all_bn230512269.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230512269/quicklook/glg_lc_medres34_bn230512269.gif
GCN 33779 table
GRB_name GRB230512A
GCN_number 33779
Detection_method AstroSat CZTI
Circular_text TITLE: GCN CIRCULAR NUMBER: 33779 SUBJECT: GRB 230512A: AstroSat CZTI detection DATE: 23/05/12 14:20:03 GMT FROM: Gaurav Waratkar at IIT Bombay P K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration: Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of GRB 230512A which was also detected by Fermi GBM (Fermi GBM Team, GCN Circ. 33778). 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 2023-05-12 06:27:47.85 UTC. The measured peak count rate associated with the burst is 2471 (+338, -103) counts/s above the background in the combined data of all quadrants, with a total of 3279 (+219, -231) counts. The local mean background count rate was 490 (+10, -12) counts/s. Using cumulative rates, we measure a T90 of 2.44 (+0.17, -0.13) s. In the preliminary analysis, we find 317 Compton events associated with this event. The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-05-12 06:27:47.85 UTC. The measured peak count rate associated with the burst is 2735 (+109, -115) counts/s above the background in the combined data of all quadrants, with a total of 6183 (+356, -346) counts. The local mean background count rate was 1667 (+6, -9) counts/s. We measure a T90 of 2.82 (+2.02, -0.27) s from the cumulative Veto light curve. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project. CZTI GRB detections are reported regularly on the payload site at: http://astrosat.iucaa.in/czti/?q=grb
GCN 33780 table
GRB_name GRB230512A
GCN_number 33780
Detection_method Fermi LAT Det
t_trigger 6:27:45.410 UTC
ra 295.4000°
decl 38.4000°
Circular_text TITLE: GCN CIRCULAR NUMBER: 33780 SUBJECT: GRB 230512A: Fermi-LAT detection DATE: 23/05/12 18:34:10 GMT FROM: N. Di Lalla at Stanford University D. J. Maheso (Johannesburg Univ.), N. Di Lalla (Stanford Univ.), Khalil T. (Johannesburg Univ.), E. Bissaldi (Politecnico and INFN Bari), N. Omodei (Stanford Univ.), D. Kocevski (NASA/MSFC) and D. Horan (IN2P3/CNRS) report on behalf of the Fermi-LAT Collaboration: At 06:27:45.41 on May 12, 2023, Fermi-LAT detected high-energy emission from GRB 230512A, which was also detected by Fermi-GBM (trigger 705565670/230512269, GCN 33778) and AstroSat (GCN 33779). The best LAT on-ground location is found to be RA, Dec = 295.4, 38.4 (degrees, J2000) with an error radius of 0.3 deg (90% containment, statistical error only). This was 45 deg from the LAT boresight at the time of the trigger. The data from the Fermi-LAT show a significant increase in the event rate that is spatially and temporally correlated with the GBM emission with high significance. The 100 MeV - 1 GeV photon flux in the time interval 0-300 s after the GBM trigger is (1.0 ± 0.3) E-05 ph/cm2/s. The estimated integrated photon index above 100 MeV is -2.15 ± 0.3. The highest-energy photon is a 1.7 GeV event with 99% probability which is observed 84 seconds after the GBM trigger. A Swift ToO has been approved for this burst. The Fermi-LAT point of contact for this burst is Dimakatso Maheso (d.j.maheso@gmail.com ) 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.
GCN 33781 table
GRB_name GRB230512A
GCN_number 33781
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 33781 SUBJECT: GRB 230512A: Tiled Swift observations DATE: 23/05/12 19:05:37 GMT FROM: Phil Evans at U of Leicester P. A. Evans (U. Leicester) reports on behalf of the Swift team: Swift has initiated a series of observations, tiled on the sky, of the Fermi/LAT GRB 230512A. Automated analysis of the XRT data will be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00111 Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. The probability of finding serendipitous sources, unrelated to the Fermi/LAT event is high: 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.
GCN 33784 table
GRB_name GRB230512A
GCN_number 33784
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 33784 SUBJECT: GRB 230512A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705565670) DATE: 23/05/12 20:21:39 GMT FROM: Tomas Ahumada at U. of Maryland Tomas Ahumada (CIT), Harsh Kumar (IITB), Viraj Karambelkar (CIT), Robert Stein (CIT), Theophile du Laz (CIT), Igor Andreoni (UMD), Michael Coughlin (UMN), Mansi Kasliwal (CIT), Simeon Reusch (DESY), Jannis Necker (DESY), Shreya Anand (CIT), report on behalf of the ZTF collaboration: We observed the localization region of the short bright GRB 230512A (trigger 705565670, GCN 33778) detected by the Gamma-Ray Burst Monitor (GBM) on the Fermi satellite with the Palomar 48 inch telescope equipped with the 47 square degree Zwicky Transient Facility (ZTF; Bellm et al., 2019; Graham et al., 2019) camera. ZTF covered 597.8 square degrees corresponding to ~86% of the probability enclosed in the localization region (GCN 33778), beginning 2 hours after the burst trigger time. Exposures reached a median depth of 21 mag in the g-band and 20.9 mag in the r-band. Two sources were found within the 95% localization region, although all are outside the 90% credible level. These are likely unrelated as they fall outside the LAT localization circulated on GCN 33780: +--------------+---------+----------+---------+------------+------------+------------+ | id | alias | ra | dec | mjd | mag |filter | |--------------+---------+----------+---------+------------|------------+------------| | ZTF23aajfoed | AT 2023ibn | 295.8501 | 51.5420 | 60076.4041 | 18.89±0.08 | g | | ZTF23aajfilx | AT 2023ibo | 267.5692 | 40.7678 | 60076.3839 | 20.22±0.19 | g | +--------------+---------+----------+---------+------------+------------+------------+ ZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA, WIS, Israel; OKC, Sweden; JSI/UMd, USA; U Washington, USA; DESY, Germany; MOST, Taiwan; UW Milwaukee, USA; LANL USA; Tokyo Tech, Japan; IITB, India; IIA, India; LJMU, UK; TTU, USA; SDSU, USA and USyd, Australia. ZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341. GROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949. Alert distribution service provided by DIRAC@UW (Patterson et al. 2019). Alert database searches are done by AMPEL (Nordin et al. 2019) and Kowalski (Duev et al. 2019). GROWTH India telescope is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA). GROWTH-India project is supported by SERB and administered by IUSSTF, under grant number IUSSTF/PIRE Program/GROWTH/2015-16 and IUCAA. -- Tomás Ahumada (he/him) Ph.D. Candidate Department of Astronomy University of Maryland, College Park NASA Goddard Space Flight Center, Code 661 B.Sc. Astronomy, Pontificia Universidad Católica de Chile
GCN 33785 table
GRB_name GRB230512A
GCN_number 33785
Detection_method Fermi GBM Det
t_trigger 6:27:45 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 33785 SUBJECT: GRB 230512A: Fermi GBM detection DATE: 23/05/12 22:33:49 GMT FROM: Oliver J Roberts at USRA/NASA S. Bala (USRA), O.J. Roberts (USRA/NASA-MSFC), B. Mailyan (Florida Tech) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 06:27:45.00 UT on 12 May 2023, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 230512A (trigger 705565670 /230512269), which was also detected by the Fermi/LAT (D. J. Maheso et al. 2023, GCN 33780). The Fermi GBM Final Real-time Localization (GCN 33778) is consistent with the LAT position. The angle from the Fermi LAT boresight at the GBM trigger time is 45 degrees. The GBM light curve consists of multiple short peaks with a duration (T90) of about 3 s (50-300 keV). The time-averaged spectrum from T0-0.064 s to T0+2.944 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.67 +/- 0.02 and the cutoff energy, parameterized as Epeak, is 1344 +/- 69 keV The event fluence (10-1000 keV) in this time interval is (1.33 +/- 0.02)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+1.54 s in the 10-1000 keV band is 16.8 +/- 0.3 ph/s/cm^2. A Band function fits the spectrum equally well with Epeak= 1215 +/- 79 keV, alpha = -0.65 +/- 0.03 and beta = -2.7 +/- 0.2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"
GCN 33786 table
GRB_name GRB230512A
GCN_number 33786
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33786 SUBJECT: GRB 230512A: GIT optical follow-up ZTF candidates DATE: 23/05/12 22:45:11 GMT FROM: Vishwajeet Swain at IIT Bombay H. Kumar (IITB), V. Swain (IITB), A. Salgundi (IITB), V. Bhalerao (IITB), G.C. Anupama (IIA), S. Barway (IIA) and K. Angail (IAO) report on behalf of the GIT team: We observed ZTF23aajfoed and ZTF23aajfilx detected by ZTF in localization region of the short GRB 230512A (Fermi GBM team, GCN 33778), with the 0.7m GROWTH-India Telescope (GIT). The observations started at 17:42:28 UT on 2023-05-12 for ZTF23aajfoed and at 17:08:25 for ZTF23aajfilx, roughly 11 hours after the Fermi GBM trigger. We obtained multiple 300s exposures in the g' and r' filters. We clearly detected the candidates at position reported by T. Ahumada et al., GCN 33784. The photometric results are follow as: ------------------------------------------------------------------------------------ Target | mjd (mid) | Filter | Total Exposure (s) | Magnitude (AB) | ------------------------------------------------------------------------------------- ZTF23aajfoed | 60076.741640 | r' | 300 | 18.87 +/- 0.06 | ZTF23aajfoed | 60076.745515 | g' | 300 | 18.84 +/- 0.07 | ZTF23aajfilx | 60076.717906 | r' | 300 | 20.16 +/- 0.07 | ZTF23aajfilx | 60076.745515 | g' | 300 | 20.23 +/- 0.07 | ----------------------------------------------------------------------------------- A comparison of GIT and ZTF observations suggests that both the targets are not evolving rapidly, indicating that they are unlikely to be GRB afterglows. The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction. The GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/.
GCN 33789 table
GRB_name GRB230512A
GCN_number 33789
Detection_method Swift-XRT Other
ra 295.4803°
decl 38.6649°
Circular_text TITLE: GCN CIRCULAR NUMBER: 33789 SUBJECT: GRB 230512A: Swift-XRT observations DATE: 23/05/13 08:06:19 GMT FROM: Phil Evans at U of Leicester J.P. Osborne (U. Leicester), A. Melandri (INAF-OAR), T. Sbarrato (INAF-OAB), P. D'Avanzo (INAF-OAB), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), D.N. Burrows (PSU), 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 the Fermi/LAT-detected burst GRB 230512A in a series of observations tiled on the sky. The total exposure time is 4.9 ks, distributed over 4 tiles; the maximum exposure at a single sky location was 2.3 ks. The data were collected between T0+45.5 ks and T0+57.3 ks, and are entirely in Photon Counting (PC) mode. Nine 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): 295.4803 = 19:41:55.26 Dec (J2000): +38.6649 = +38:39:53.6 Error: 4.2 arcsec (radius, 90% conf. [Enhanced position]) Count-rate: (8.8 [+3.9, -3.0])e-3 ct s^-1 Distance: 980 arcsec from Fermi/LAT position. Flux: (5.1 [+2.2, -1.8])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV) Source 3: RA (J2000): 295.5430 = 19:42:10.33 Dec (J2000): +38.7526 = +38:45:09.4 Error: 5.5 arcsec (radius, 90% conf. [Enhanced position]) Count-rate: 0.0176 [+0.0056, -0.0047] ct s^-1 Distance: 1331 arcsec from Fermi/LAT position. Flux: (3.57 [+1.13, -0.95])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV) Source 5: RA (J2000): 295.2060 = 19:40:49.43 Dec (J2000): +38.4686 = +38:28:07.1 Error: 6.2 arcsec (radius, 90% conf.) Count-rate: 0.0105 [+0.0042, -0.0034] ct s^-1 Distance: 600 arcsec from Fermi/LAT position. Source 6: RA (J2000): 295.7616 = 19:43:2.79 Dec (J2000): +38.3644 = +38:21:51.9 Error: 3.9 arcsec (radius, 90% conf. [Enhanced position]) Count-rate: (6.7 [+3.5, -2.6])e-3 ct s^-1 Distance: 1028 arcsec from Fermi/LAT position. Source 7: RA (J2000): 295.0895 = 19:40:21.48 Dec (J2000): +38.4348 = +38:26:05.5 Error: 6.8 arcsec (radius, 90% conf.) Count-rate: (5.4 [+3.3, -2.4])e-3 ct s^-1 Distance: 884 arcsec from Fermi/LAT position. Source 8: RA (J2000): 295.3130 = 19:41:15.11 Dec (J2000): +38.4565 = +38:27:23.3 Error: 5.1 arcsec (radius, 90% conf. [Enhanced position]) Count-rate: (8.7 [+4.1, -3.2])e-3 ct s^-1 Distance: 318 arcsec from Fermi/LAT position. Source 9: RA (J2000): 295.2484 = 19:40:59.62 Dec (J2000): +38.1016 = +38:06:05.7 Error: 7.7 arcsec (radius, 90% conf.) Count-rate: (5.5 [+3.1, -2.3])e-3 ct s^-1 Distance: 1156 arcsec from Fermi/LAT position. Source 10: RA (J2000): 295.1589 = 19:40:38.13 Dec (J2000): +38.4685 = +38:28:06.6 Error: 6.1 arcsec (radius, 90% conf.) Count-rate: (9.8 [+5.8, -4.3])e-3 ct s^-1 Distance: 723 arcsec from Fermi/LAT position. Source 11: RA (J2000): 295.2125 = 19:40:50.99 Dec (J2000): +38.0868 = +38:05:12.5 Error: 4.5 arcsec (radius, 90% conf. [Enhanced position]) Count-rate: (9.5 [+4.1, -3.2])e-3 ct s^-1 Distance: 1245 arcsec from Fermi/LAT position. Flux: (3.3 [+1.4, -1.1])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV) Two catalogued sources were also detected. The results of the XRT-team automatic analysis of the tiled XRT observations, including a position-specific upper limit calculator, are available at https://www.swift.ac.uk/xrt_products/TILED_GRB00111. This circular is an official product of the Swift-XRT team.
GCN 33795 table
GRB_name GRB230512A
GCN_number 33795
Detection_method Fermi LAT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 33795 SUBJECT: GRB 230512A: GRBAlpha detection DATE: 23/05/14 08:29:43 GMT FROM: Marianna Dafčíková at Masaryk University <500025@mail.muni.cz> M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), yyT. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration. The GRB 230512A (Fermi/GBM detection: GCN 33778; Fermi/LAT detection: GCN 33780; AstroSat detection: GCN 33779) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023; arXiv:2302.10048). The detection was confirmed at the peak time 2023-05-12 06:27:47 UTC. The T90 duration measured by GRBAlpha is 4 s and the overall significance during T90 reaches 11 sigma. The light curve obtained by GRBAlpha is available here: https://grbalpha.konkoly.hu/static/share/GRB230512A_GCN.pdf All GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ GRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume.
GCN 33796 table
GRB_name GRB230512A
GCN_number 33796
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33796 SUBJECT: GRB 230512A: Kitab possible afterglow candidate DATE: 23/05/14 12:41:26 GMT FROM: Alexei Pozanenko at IKI, Moscow S. Belkin (IKI), A. Schmalz (KIAM), A. Pozanenko (IKI), N. Pankov (HSE), Sh. Ehgamberdiev (UBAI) report on behalf of IKI-GRB-FuN: We observed the field of Fermi LAT localization (Maheso et al., GCN 33780) of short bright GRB 230512A (Fermi GBM team, GCN 33778; detected also by AstroSat GCN 33779, and GRBAlpha GCN 33795) with Kitab RC-36 telescope. Observation in Clear filter started on May, 12 (UT) 19:17:32 and continued on May, 13 (UT) 20:49:59. We cover XRT sources ## 2,4,5,7,8,9,10,11 (Osborne et al., GCN 33789). Within the XRT #5 error circle, we detected a possible optical source on May 12 and did not detect the source on May 13. The source is also absent in PS1 catalog. The coordinate of the source are (J2000) 19:40:49.49 +38:28:07.4 with uncertainness of 0.5 arcsec in both coordinates. The nearest PS object is 2.5 arcses East with r'=22.14. Preliminary photometry of the source in combined images is following Date, UT start, t-T0, Exp., Filter, OT, Err, UL(3 sigma) (mid, days) 2023-05-12 19:17:32 0.57624 120*60 Clear 19.43 0.25 19.7 2023-05-13 20:49:59 1.64044 120*60 Clear n/d n/d 20.0 The photometry is based on nearby USNO-B1.0 stars, R2 magnitude and not corrected for Galaxy extinction. USNO-B1.0 stars RA Dec R2 19:40:50.8094400 +38:29:37.881600 14.55 19:40:53.3748000 +38:29:06.702000 15.30 19:40:46.4635200 +38:06:31.770000 14.15 19:41:16.4054400 +38:09:39.092400 15.80 Taking photometry in the first epoch and an upper limit on the second epoch the index of power law decay is less than -0.5.
GCN 33797 table
GRB_name GRB230512A
GCN_number 33797
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33797 SUBJECT: GRB 230512A: GIT non detection of afterglow candidate DATE: 23/05/14 16:41:15 GMT FROM: Vishwajeet Swain at IIT Bombay V. Swain (IITB), H. Kumar (IITB), A. Salgundi (IITB), V. Bhalerao (IITB), G.C. Anupama (IIA), S. Barway (IIA) and K. Angail (IAO) report on behalf of the GIT team: We observed the region of short GRB 230512A (Fermi GBM team, GCN 33778 and D. J. Maheso et al., GCN 33780), with the 0.7m GROWTH-India Telescope (GIT) covering the position of afterglow detected by S. Belkin et al., GCN 33796, . The observations started at 20:41:30 UT on 2023-05-12, 14.22 hours after the Fermi GBM trigger and 1.4 hours after the commencement of Kitab RC-36 observations (Belkin et al., GCN #33796). We obtained two exposures of 400s each in the r' band, coincidentally overlapping with the end of their first epoch. We later imaged the field in the g' band as well, with 2x400s exposures. We search individual images and the stacked image for an afterglow, but find no afterglow candidates. In particular, we do not detect the optical afterglow emission reported by S. Belkin et al., GCN 33796, despite our images having sufficient depth. Our upper limits are as follows: ----------------------------------------------------------------------------- JD (mid) | T_mid-T0(hrs) |T_mid - T(Kitab)|Filter | Total Exposure (s) | Lim_mag (5-sigma) | ----------------------------------------------------------------------------- 2460077.364615665 | 14.28 | 1.46 | r' | 2 X 400 (stacked) | >20.39 | 2460077.43835897 | 15.88 | 3.05 | g' | 2 x 400 (stacked) | >21.08 | ---------------------------------------------------------------------------- We note that there is no known minor planet at this location in MPC. The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction. The GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/.
GCN 33798 table
GRB_name GRB230512A
GCN_number 33798
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33798 SUBJECT: GRB 230512A: Liverpool Telescope observations DATE: 23/05/14 17:03:28 GMT FROM: Ben Gompertz at U of Birmingham B. P. Gompertz (U. Birmingham), D. B. Malesani (U. Radboud and DAWN/NBI) and A. J. Levan (U. Radboud) report: We tiled part of the LAT localisation (Maheso et al., GCN 33780) of GRB 230512A (Fermi GBM Team, GCN 33778; Navaneeth et al., GCN 33779; Dafcikova et al., GCN 33795) with the IO:O optical camera on the 2m robotic Liverpool Telescope. XRT source 5 (Osborne et al., GCN 33789) was covered by an observation beginning on May 13, 2023 at 03:10:22 UT and consisting of a series of 6x150 s exposures in the SDSS r' filter. We detect no source at the position of the candidate optical counterpart reported by Kitab (Belkin et al., GCN 33796) to a 3-sigma limit of r’ > 22.15, ~7.5 hours after the reported detection. We also detect the PS1 source at a magnitude consistent with the catalogued value. No other candidate optical counterparts have been identified in our imaging, which also covers XRT sources 8 and 10, to typical limits of r' > 22. Analysis is ongoing. Magnitudes are in the AB system, calibrated against nearby PS1 stars (Chambers et al., 2016), and are not corrected for extinction along the line of sight.
GCN 33799 table
GRB_name GRB230512A
GCN_number 33799
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 33799 SUBJECT: GRB 230512A: Zwicky Transient Facility non-detection of GRB afterglow candidate DATE: 23/05/14 17:10:39 GMT FROM: Tomas Ahumada at U. of Maryland Tomas Ahumada (CIT), Michael Coughlin (UMN), Igor Andreoni (UMD), Varun Bhalerao (IITB) on behalf of the ZTF collaboration: We analyze the ZTF images containing the afterglow candidate (Belkin et al., GCN Circ. 33796) and no sources were found up to the following limits: UTC observation , t-t0 , filter, upper limit 2023-05-13 06:33:14, 1.003 , r , 21.02 mag 2023-05-13 06:25:09, 0.998 , g , 20.83 mag ZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA, WIS, Israel; OKC, Sweden; JSI/UMd, USA; U Washington, USA; DESY, Germany; MOST, Taiwan; UW Milwaukee, USA; LANL USA; Tokyo Tech, Japan; IITB, India; IIA, India; LJMU, UK; TTU, USA; SDSU, USA and USyd, Australia. ZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341. GROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949. Alert distribution service provided by DIRAC@UW (Patterson et al. 2019). Alert database searches are done by AMPEL (Nordin et al. 2019) and Kowalski (Duev et al. 2019). GROWTH India telescope is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA). GROWTH-India project is supported by SERB and administered by IUSSTF, under grant number IUSSTF/PIRE Program/GROWTH/2015-16 and IUCAA. -- Tomás Ahumada (he/him) Ph.D. Candidate Department of Astronomy University of Maryland, College Park NASA Goddard Space Flight Center, Code 661 B.Sc. Astronomy, Pontificia Universidad Católica de Chile
GCN 33800 table
GRB_name GRB230512A
GCN_number 33800
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33800 SUBJECT: GRB 230512A: Nanshan/NEXT non-detection of GRB afterglow candidate DATE: 23/05/14 23:03:22 GMT FROM: Dong Xu at NAOC/CAS S.Q. Jiang, T.H. Lu, S.Y. Fu, X. Liu, Z.P. Zhu, D. Xu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report: We observed the field of Fermi LAT localization (Maheso et al., GCN 33780) of short bright GRB 230512A (Fermi GBM team, GCN 33778; AstroSat, GCN 33779 and GRBAlpha, GCN 33795) using the NEXT-0.6m optical telescope located at Nanshan, Xinjiang, China. No optical source is detected in our stacked images at the XRT source 5 position. Preliminary photometric results are as follows: T_mid-T0(day) Filter Upper_Limit(3-sigma) 0.537 r 20.7 1.543 r 21.8 1.563 z 20.0 calibrated with the nearby PS1 stars and not corrected for Galactic extinction. The NEXT's first epoch image doesn't reveal the Kitab candidate (Belkin et al., GCN 33796), although it is deeper. Some other XRT sources are also covered, and so far no credible optical afterglow candidate can be claimed.
GCN 33802 table
GRB_name GRB230512A
GCN_number 33802
Detection_method IPN Triangulation
t_trigger 6:27:45 UTC
ra 295.4160°
decl 38.4139°
Circular_text TITLE: GCN CIRCULAR NUMBER: 33802 SUBJECT: IPN triangulation of GRB 230512A DATE: 23/05/15 10:17:05 GMT FROM: Dmitry Svinkin at Ioffe Institute D. Svinkin, D. Frederiks, A. Ridnaia, A. Lysenko, and T. Cline on behalf of the Konus-Wind team, A. Goldstein, M. S. Briggs, C. Wilson-Hodge, and E. Burns on behalf of the Fermi GBM team, and S. Barthelmy, J. Cummings, H. Krimm, D. Palmer, and A. Tohuvavohu on behalf of the Swift-BAT team, report: The bright GRB 230512A (Fermi-GBM detection: The Fermi GBM team, GCN Circ. 33778; Roberts et al., GCN Circ. 33785; AstroSat-CZTI detection: Navaneeth et al., GCN Circ. 33779; Fermi-LAT detection: Maheso et al., GCN Circ. 33780; GRBAlpha detection: Dafcikova et al., GCN Circ. 33795) was detected by Fermi (GBM trigger 705565670; LAT), AstroSat (CZTI), Konus-Wind, GRBAlpha, and Swift (BAT) at about 23265 s UT (06:27:45). The burst was outside the coded field of view of the BAT. We have triangulated it to a Konus-GBM annulus centered at RA(2000)=252.326 deg (16h 49m 18s) Dec(2000)=-21.096 deg (-21d 05' 46"), whose radius is 71.928 +/- 0.057 deg (3 sigma). The LAT position reported by Maheso et al. (GCN Circ. 33780) is consistent with the annulus. The annulus combined with the LAT (90 % containment, statistical-only) error circle gives the following error box: --------------------------------- RA(2000), deg Dec(2000), deg --------------------------------- Center: 295.4160 +38.4139 Corners: 295.6484 +38.1720 295.7385 +38.2604 295.1883 +38.6501 295.0849 +38.5708 --------------------------------- The error box area is 242.2 sq. arcmin (a factor of ~4 smaller than that of the LAT error circle), and its maximum dimension is 0.6 deg (the minimum one is 6.8 arcmin). The Sun distance was 96 deg. This box may be improved. The Swift-XRT sources #2, 4, 8 (https://www.swift.ac.uk/xrt_products/TILED_GRB00111/) are inside the error box. The OT candidate (Belkin et al., GCN Circ. 33796) is outside the error box. A triangulation map and HEALPix FITS file are posted at http://www.ioffe.ru/LEA/GRBs/GRB230512_T23265/IPN/ The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.
GCN 33808 table
GRB_name GRB230512A
GCN_number 33808
Detection_method IPN Triangulation
ra 295.6230°
decl 38.2670°
Circular_text TITLE: GCN CIRCULAR NUMBER: 33808 SUBJECT: Improved IPN triangulation of GRB 230512A DATE: 23/05/17 12:02:03 GMT FROM: Dmitry Svinkin at Ioffe Institute 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, C. Wilson-Hodge, and E. Burns 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: Using the BepiColombo (MGNS) data we have improved the previous IPN box (Svinkin et al., GCN Circ. 33802), The coordinates of the updated 3 sigma error box are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 295.623 (19h 42m 30s) +38.267 (+38d 16' 00") Corners: 295.645 (19h 42m 35s) +38.328 (+38d 19' 39") 295.609 (19h 42m 26s) +38.353 (+38d 21' 10") 295.601 (19h 42m 24s) +38.206 (+38d 12' 20") 295.637 (19h 42m 33s) +38.180 (+38d 10' 49") --------------------------------------------- The error box area is 15 sq. arcmin, and its maximum dimension is 10 arcmin (the minimum one is 1.7 arcmin). The Sun distance was 96 deg. This box may be further improved. None of the optical and X-ray transients found during the burst follow-up (GCNs 33784, 33789, 33796) are inside the box. An updated triangulation map and HEALPix FITS files are posted at http://www.ioffe.ru/LEA/GRBs/GRB230512_T23265/IPN/