GRB240918A

This page lists all entries on GRB240918A in GRBweb

Summary Fermi GBM IPN GCN 37549 GCN 37550 GCN 37560

Summary table
Variable Value Source
GRB_name_Fermi GRB240918872
T0 20:55:06.809 UTC Fermi_GBM
ra 143.2792° IPN
decl -17.4333° IPN
pos_error 5.60e+00° IPN
T90 11.264 s Fermi_GBM
T90_error 2.187 s Fermi_GBM
T90_start 20:55:06.809 UTC Fermi_GBM
fluence 1.57e-06 erg/cm² Fermi_GBM
fluence_error 2.75e-08 erg/cm² Fermi_GBM
T100 11.264 s
GBM_located False
mjd 60571.87160658565 Fermi_GBM
Fermi GBM table
GRB_name_Fermi GRB240918872
trigger_name bn240918872
ra 221.5700°
decl 17.0000°
pos_error 6.74e+00°
datum 2024-09-18
t_trigger 20:55:11.161 UTC
T90 11.264 s
T90_error 2.187 s
T90_start 20:55:06.809 UTC
fluence 1.57e-06 erg/cm²
fluence_error 2.75e-08 erg/cm²
flux_1024 2.77e+00 erg/cm²/s
flux_1024_error 2.46e-01 erg/cm²/s
flux_1024_time 1.92e+00 erg/cm²/s
flux_64 5.02e+00 erg/cm²/s
flux_64_error 1.25e+00 erg/cm²/s
IPN table
GRB_name GRB240918A
ra 143.2792°
decl -17.4333°
pos_error 5.60e+00°
GCN 37549 table
GRB_name GRB240918A
GCN_number 37549
Detection_method Fermi GBM final loc
t_trigger 20:55:11 UTC
ra 221.6000°
decl 17.0000°
Circular_text TITLE: GCN CIRCULAR NUMBER: 37549 SUBJECT: GRB 240918A: Fermi GBM Final Real-time Localization DATE: 24/09/18 21:04:21 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM The Fermi GBM team reports the detection of a likely LONG GRB At 20:55:11 UT on 18 Sep 2024, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 240918A (trigger 748385716.160644 / 240918872). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 221.6, Dec = 17.0 (J2000 degrees, equivalent to J2000 14h 46m, 17d 00'), with a statistical uncertainty of 10.4 degrees. The angle from the Fermi LAT boresight is 86.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240918872/quicklook/glg_skymap_all_bn240918872.png The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240918872/quicklook/glg_healpix_all_bn240918872.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240918872/quicklook/glg_lc_medres34_bn240918872.gif
GCN 37550 table
GRB_name GRB240918A
GCN_number 37550
Detection_method Fermi GBM Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 37550 SUBJECT: Fermi GRB 240918A: Global MASTER-Net observations report DATE: 24/09/18 23:30:50 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko, G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gress, N.M. Budnev, O.Ershova (Irkutsk State University, API), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich (Blagoveschensk Educational State University) MASTER-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 240918A ( Fermi GBM team, GCN 37549) errorbox 8469 sec after notice time and 8476 sec after trigger time at 2024-09-18 23:16:27 UT, with upper limit up to 13.1 mag. Observations started at twilight. The observations began at zenith distance = 73 deg. The sun altitude is -11.0 deg. The galactic latitude b = 61 deg., longitude l = 18 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2607032 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 8507 | 2024-09-18 23:16:27 | MASTER-OAFA | (14h 49m 57.03s , +19d 01m 43.5s) | C | 60 | 12.0 | 8770 | 2024-09-18 23:20:50 | MASTER-OAFA | (15h 06m 05.69s , +19d 01m 26.3s) | C | 60 | 12.7 | 8990 | 2024-09-18 23:24:30 | MASTER-OAFA | (14h 48m 30.08s , +15d 13m 06.5s) | C | 60 | 13.1 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.
GCN 37560 table
GRB_name GRB240918A
GCN_number 37560
Detection_method INTEGRAL
Circular_text TITLE: GCN CIRCULAR NUMBER: 37560 SUBJECT: GRB 240918A and GRB 240918B : INTEGRAL SPI ACS LIGHT CURVE DATE: 24/09/19 23:14:33 GMT FROM: Devraj Pawar at R. J. College, Mumbai - 86, India Devraj Pawar (R. J. College, Mumbai-86, India) on behalf of a collaboration studying transients. GRB 240918A and GRB 240918B were reported by the Fermi GBM team in GCN 37549 and GCN 37558 respectively. We analyzed the INTEGRAL SPI ACS data around the T0 given in GCN 37549 and detected two peaks separated by ~108 seconds in the light curve. These events occur at the times reported in GCN 37549 and GCN 37558. SPI ACS is sensitive above 80 keV : the peak of the first burst is at ~3550 counts/s and peak count rate of the second burst is 3800 counts/s. The steady count rate preceding the events is around 3350 counts/s. The count rate is affected by the instruments orientation with respect to the direction of the sources and hence the relative intensity of the two bursts cannot be compared with the analysis done so far. GRB 240918A is not visually detected with the 0.05 s resolution of the INTEGRAL SPI ACS, hence we time averaged the light curve. The light curves at various time resolutions and the burst profiles are given in the link below and any further analysis will be shared on the same link : [GRB 240918A and GRB 240918B : INTEGRAL SPI ACS LIGHT CURVES](https://docs.google.com/document/d/15b887kxPSdQVyT9NLfZZzb8XMLhijewiSY8KHXPTdhI/edit?usp=sharing) This work is based on observations with INTEGRAL, an ESA project with instruments and a science data center funded by ESA member states (especially the PI countries: Denmark, France, Germany, Italy, Switzerland, Spain), and with the participation of Russia and the USA. The SPI-ACS detector system has been provided by MPE Garching/Germany.