GRB221025A

This page lists all entries on GRB221025A in GRBweb

Summary Fermi GBM IPN GCN 32843 GCN 32851 GCN 32853 GCN 32865

Summary table
Variable Value Source
GRB_name_Fermi GRB221025040
T0 0:58:18 UTC GCN_circulars,Fermi GBM Det
ra 133.3792° IPN
decl 10.9833° IPN
pos_error 1.27e+00° IPN
T90 0.448 s Fermi_GBM
T90_error 0.143 s Fermi_GBM
T90_start 0:58:18.355 UTC Fermi_GBM
fluence 1.61e-06 erg/cm² Fermi_GBM
fluence_error 2.39e-08 erg/cm² Fermi_GBM
T100 0.803 s
GBM_located False
mjd 59877.04048611111 GCN_circulars,Fermi GBM Det
Fermi GBM table
GRB_name_Fermi GRB221025040
trigger_name bn221025040
ra 133.4000°
decl 11.0000°
pos_error 6.17e+00°
datum 2022-10-25
t_trigger 0:58:18.419 UTC
T90 0.448 s
T90_error 0.143 s
T90_start 0:58:18.355 UTC
fluence 1.61e-06 erg/cm²
fluence_error 2.39e-08 erg/cm²
flux_1024 3.86e+00 erg/cm²/s
flux_1024_error 2.00e-01 erg/cm²/s
flux_1024_time -3.20e-01 erg/cm²/s
flux_64 1.33e+01 erg/cm²/s
flux_64_error 9.17e-01 erg/cm²/s
IPN table
GRB_name GRB221025A
ra 133.3792°
decl 10.9833°
pos_error 1.27e+00°
GCN 32843 table
GRB_name GRB221025A
GCN_number 32843
Detection_method Fermi LAT Det
t_trigger 0:58:18.420 UTC
ra 133.4000°
decl 11.0000°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32843 SUBJECT: GRB 221025A: Fermi-LAT detection DATE: 22/10/25 11:43:09 GMT FROM: Makoto Arimoto at Tokyo Inst of Tech Arimoto M. (Kanazawa University) Pillera R. (Politecnico and INFN Bari), and Maheso D. (Johannesburg Univ.) report on behalf of the Fermi-LAT team: At 00:58:18.42 on October, 25, 2022 Fermi-LAT detected high-energy emission from GRB 221025A, GBM trigger 221025041 / 688352303 at 00:58:18.42 UT. The best LAT on-ground location is found to be RA, Dec = 133.4, 11.0 (J2000) with an error radius of 1.3 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 trigger with high significance. The 100 MeV - 1 GeV photon flux in the time interval 0-200 s after the GBM trigger is (2.1 +/- 0.6)E-05 ph/cm2/s. The estimated integrated photon index above 100 MeV is -2.3 +/- 0.3. The highest-energy photon is a 1.3 GeV event with 93% probability which is observed 3 seconds after the GBM trigger. A Swift ToO has been requested for this burst. The Fermi-LAT point of contact for this burst is Dimakatso Jeannett 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 32851 table
GRB_name GRB221025A
GCN_number 32851
Detection_method Fermi GBM Det
t_trigger 0:58:18 UTC
ra 128.9000°
decl 2.2000°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32851 SUBJECT: GRB 221025A: Fermi GBM Observation DATE: 22/10/25 16:52:20 GMT FROM: Joshua Wood at MSFC/Fermi-GBM J. Wood (NASA/MSFC) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 00:58:18 UT on 25 October 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 221025A (trigger 688352303 / 221025040). which was also detected by Fermi-LAT (Arimoto M. et al. 2022, GCN 32843). The Fermi GBM on-ground location is consistent with the Fermi-LAT position. The on-ground calculated location, using the GBM trigger data, is RA = 128.9, DEC = +2.2 (J2000 degrees, equivalent to 08h 36m, +02d 12'), with an uncertainty of 6.8 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 is 48.5 degrees. The GBM light curve consists of a single pulse with a duration (T90) of about 0.4 s (50-300 keV). The time-averaged spectrum from T0+0.0 to T0+0.8 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.4 +/- 0.1 and the cutoff energy, parameterized as Epeak, is 1680 +/- 345 keV. The event fluence (10-1000 keV) in this time interval is (1.7 +/- 0.1)E-06 erg/cm^2. The 64-ms peak photon flux measured starting from T0+0.3 s in the 10-1000 keV band is 13.3 +/- 0.9 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 32853 table
GRB_name GRB221025A
GCN_number 32853
Detection_method AstroSat CZTI
Circular_text TITLE: GCN CIRCULAR NUMBER: 32853 SUBJECT: GRB 221025A: AstroSat CZTI detection DATE: 22/10/26 13:42:23 GMT FROM: Gaurav Waratkar at IIT,Bombay R. Gopalakrishnan (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration: Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a short GRB 221025A which was also detected by Fermi-GBM (Wood et al,. GCN 32851) and Fermi-LAT (Arimoto et al,. GCN 32843). The source was clearly detected in the 20-200 keV energy range. The light curve peaks at 2022-10-25 00:58:18.6 UTC. The measured peak count rate associated with the burst is 904 (+212, -102) counts/s above the background in the combined data of all quadrants, with a total of 313 (+62, -63) counts. The local mean background count rate was 435 (+8, -12) counts/s. Using cumulative rates, we measure a T90 of 0.45 (+0.6, -0.2) s. It was also detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. Due to the intrinsic 1 s binning of veto data, we cannot reliably estimate a T90 from it. CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.
GCN 32865 table
GRB_name GRB221025A
GCN_number 32865
Detection_method IPN Triangulation
t_trigger 0:58:18 UTC
ra 134.3730°
decl 13.0680°
Circular_text TITLE: GCN CIRCULAR NUMBER: 32865 SUBJECT: IPN triangulation of GRB 221025A (short) DATE: 22/10/27 14:34:24 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, E. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, report: The short-duration GRB 221025A (Fermi-LAT detection: Arimoto et al., GCN Circ. 32843; Fermi-GBM detection: Wood and Meegan, GCN Circ. 32851; AstroSat-CZTI detection: Gopalakrishnan et al., GCN Circ. 32853) was detected by Fermi (GBM trigger 688352303), INTEGRAL (SPI-ACS), Konus-Wind, AstroSat (CZTI), and GECAM-B (trigger tn221025_005818_fb) at about 3498 s UT (00:58:18). We have triangulated it to a preliminary, 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 134.373 (08h 57m 29s) +13.068 (+13d 04' 07") Corners: 133.601 (08h 54m 24s) +10.772 (+10d 46' 20") 133.259 (08h 53m 02s) +10.806 (+10d 48' 20") 135.172 (09h 00m 41s) +15.363 (+15d 21' 46") 135.522 (09h 02m 05s) +15.330 (+15d 19' 48") --------------------------------------------- The error box area is 1.6 sq. deg, and its maximum dimension is 5.03 deg (the minimum one is 19.44 arcmin). The Sun distance was 78 deg. This localization may be improved. The IPN localization is consistent with, but reduces the area of, the Fermi-GBM final localization (glg_healpix_all_bn221025040_v00). A triangulation map and HEALPix FITS file are posted at http://www.ioffe.ru/LEA/GRBs/GRB221025_T03498/IPN/ The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.