GRB230919A

This page lists all entries on GRB230919A in GRBweb

Summary Fermi GBM IPN GCN 34737 GCN 34742 GCN 34747 GCN 34750 GCN 34752

Summary table
Variable Value Source
GRB_name_Fermi GRB230919707
T0 16:58:23 UTC GCN_circulars,Fermi GBM final loc
ra 71.6208° IPN
decl 44.0833° IPN
pos_error 3.60e+00° IPN
T90 2.944 s Fermi_GBM
T90_error 0.834 s Fermi_GBM
T90_start 16:58:23.793 UTC Fermi_GBM
fluence 1.53e-06 erg/cm² Fermi_GBM
fluence_error 2.22e-08 erg/cm² Fermi_GBM
T100 3.737 s
GBM_located False
mjd 60206.70721064815 GCN_circulars,Fermi GBM final loc
Fermi GBM table
GRB_name_Fermi GRB230919707
trigger_name bn230919707
ra 58.1900°
decl 41.1700°
pos_error 3.90e+00°
datum 2023-09-19
t_trigger 16:58:23.857 UTC
T90 2.944 s
T90_error 0.834 s
T90_start 16:58:23.793 UTC
fluence 1.53e-06 erg/cm²
fluence_error 2.22e-08 erg/cm²
flux_1024 6.88e+00 erg/cm²/s
flux_1024_error 3.43e-01 erg/cm²/s
flux_1024_time 1.28e-01 erg/cm²/s
flux_64 1.22e+01 erg/cm²/s
flux_64_error 2.09e+00 erg/cm²/s
IPN table
GRB_name GRB230919A
ra 71.6208°
decl 44.0833°
pos_error 3.60e+00°
GCN 34737 table
GRB_name GRB230919A
GCN_number 34737
Detection_method Fermi GBM final loc
t_trigger 16:58:23 UTC
ra 58.2000°
decl 41.2000°
Circular_text TITLE: GCN CIRCULAR NUMBER: 34737 SUBJECT: GRB 230919A: Fermi GBM Final Real-time Localization DATE: 23/09/19 17:06:22 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM The Fermi GBM team reports the detection of a likely LONG GRB At 16:58:23 UT on 19 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230919A (trigger 716835508.857072 / 230919707). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 58.2, Dec = 41.2 (J2000 degrees, equivalent to J2000 03h 52m, 41d 12'), with a statistical uncertainty of 6.7 degrees. The angle from the Fermi LAT boresight is 120.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230919707/quicklook/glg_skymap_all_bn230919707.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/bn230919707/quicklook/glg_healpix_all_bn230919707.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230919707/quicklook/glg_lc_medres34_bn230919707.gif
GCN 34742 table
GRB_name GRB230919A
GCN_number 34742
Detection_method AstroSat CZTI
Circular_text TITLE: GCN CIRCULAR NUMBER: 34742 SUBJECT: GRB 230919A: AstroSat CZTI detection DATE: 23/09/20 13:42:29 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 230919A which was also detected by Fermi-GBM (Fermi GBM Team, GCN Circ. 34737). The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2023-09-19 16:58:23.95 UTC. The measured peak count rate associated with the burst is 1118 (+205, -166) counts/s above the background in the combined data of all quadrants, with a total of 921 (+115, -92) counts. The local mean background count rate was 406 (+10, -15) counts/s. Using cumulative rates, we measure a T90 of 1.58 (+1.38, -0.23) s. We caution that there are two 0.3 s readout dead time windows in CZTI data immediately after the detection of the burst. Hence, the T90 can be as large as 2.96 s for this GRB, with a lower limit of 1.35 s as estimated above by cumulative rates. The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-09-19 16:58:23.55 UTC. The measured peak count rate associated with the burst is 1196 (+82, -86) counts/s above the background in the combined data of all quadrants, with a total of 1796 (+193, -200) counts. The local mean background count rate was 1280 (+6, -6) counts/s. We measure a T90 of 2.1 (+1.2, -0.5) s from the cumulative Veto light curve. Note that this result is limited due to the 1 s native resolution of veto data. 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 34747 table
GRB_name GRB230919A
GCN_number 34747
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 34747 SUBJECT: GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV DATE: 23/09/20 17:51:55 GMT FROM: Jimmy DeLaunay at University of Alabama James DeLaunay (U Alabama), Aaron Tohuvavohu (U Toronto), Samuele Ronchini (PSU), Gayathri Raman (PSU), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC) report: Swift/BAT did not localize GRB 230919A onboard (T0: 2023-09-19T16:58:23.86 UTC, Fermi trig 716835508, AstroSat CZTI GCN 34742) 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 90 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground. The BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), performed on the temporal window [T0-20 s, T0+20 s], detects the burst with a sqrt(TS) of 16.6 in a 1.5 s analysis time bin, starting at T0 - 0.2 s. NITRATES results are consistent with a burst coming from outside the FOV, with DeltaLLHOut of -0.6 and are consistent with Fermi GBM's localization (GCN 34737). See Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretation of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut. GUANO is a fully autonomous, extremely low latency, spacecraft commanding pipeline designed for targeted recovery of BAT event mode data around the times of compelling astrophysical events to enable more sensitive GRB searches. A live reporting of Swift/BAT event data recovered by GUANO can be found at: https://www.swift.psu.edu/guano/
GCN 34750 table
GRB_name GRB230919A
GCN_number 34750
Detection_method Fermi GBM Det
t_trigger 16:58:23.860 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 34750 SUBJECT: GRB 230919A: Fermi GBM Observation DATE: 23/09/20 20:49:41 GMT FROM: Lorenzo Scotton at UAH L. Scotton (UAH), C. Fletcher (USRA) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 16:58:23.86 UT on 19 September 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230919A (trigger 716835508/230919707). which was also detected by AstroSat (Navaneeth et al. 2023, GCN 34742) and Swift/BAT-GUANO (DeLaunay et al. 2023, GCN 34747). The Fermi GBM Final Real-time Localization was reported in GCN 34737. The angle from the Fermi LAT boresight is 120 degrees. The GBM light curve consists of multiple peaks with a duration (T90) of about 2.9s. The time-averaged spectrum from T0-0.06 to T0+1.34 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.74 +/- 0.06 and the cutoff energy, parameterized as Epeak, is 2023 +/- 271 keV. A Band function fits the spectrum equally well with Epeak = 1617 +/- 352 keV, alpha = -0.68 +/- 0.08 and beta = -2.43 +/- 0.32. The event fluence (10-1000 keV) in this time interval is (3.3 +/- 0.1)E-06 erg/cm^2. The 64-msec peak photon flux measured starting from T0+0.58 s in the 10-1000 keV band is 12 +/- 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/"
GCN 34752 table
GRB_name GRB230919A
GCN_number 34752
Detection_method IPN Triangulation
t_trigger 16:58:23 UTC
ra 71.6200°
decl 44.0760°
Circular_text TITLE: GCN CIRCULAR NUMBER: 34752 SUBJECT: IPN triangulation of GRB 230919A (short) DATE: 23/09/20 21:46:04 GMT FROM: Anna Ridnaia at Ioffe Institute 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, C. Wilson-Hodge, and E. Burns 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 short-duration GRB 230919A (Fermi-GBM detection: The Fermi GBM team, GCN Circ. 34737; Scotton et al., GCN Circ. 34750; AstroSat CZTI detection: Navaneeth et al., GCN Circ. 34742; Swift/BAT-GUANO detection: DeLaunay et al., GCN Circ. 34747) has been detected by Fermi (GBM trigger 716835508), Konus-Wind, Mars-Odyssey (HEND), Swift (BAT), and AstroSat (CZTI), so far, at about 61103 s UT (16:58:23). 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: 71.620 (04h 46m 29s) +44.076 (+44d 04' 35") Corners: 70.812 (04h 43m 15s) +45.562 (+45d 33' 43") 70.802 (04h 43m 12s) +45.703 (+45d 42' 10") 72.402 (04h 49m 37s) +42.484 (+42d 29' 04") 72.411 (04h 49m 39s) +42.324 (+42d 19' 28") --------------------------------------------- The error box area is 543 sq. arcmin, and its maximum dimension is 3.6 deg (the minimum one is 3 arcmin). The Sun distance was 100 deg. The IPN localization is consistent with, but reduces the area of, the Fermi-GBM final localization (GCN Circ. 34737). This localization may be improved. A triangulation map and HEALPix FITS file are posted at http://www.ioffe.ru/LEA/GRBs/GRB230919_T61103/IPN/ The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.