{
  "submitter": "Elisabetta Bissaldi at Politecnico and INFN Bari <elisabetta.bissaldi@ba.infn.it>",
  "format": "text/plain",
  "submittedHow": "web",
  "body": "E. Bissaldi (Politecnico and INFN Bari) and C. Meegan (UAH)\nreport on behalf of the Fermi GBM Team:\n\n\n\"At 12:19:52.14 UT on 17 November 2025, the Fermi Gamma-Ray Burst Monitor (GBM)\ntriggered and located GRB 251117A (trigger 785074797 / 251117514),\nwhich was also detected by the Fermi LAT (Holzmann Airasca et al., GCN 42729), \nSVOM/GRM (Wang et al., GCN 42731) and Swift/BAT-GUANO (DeLaunay et al. 2025, GCN 42732).\n\nThe GBM on-ground location (GCN 42719) is consistent with the Fermi LAT position.\nThe angle from the Fermi LAT boresight at the GBM trigger time is 50 degrees.\n\nThe GBM light curve consists of a multi-peaked emission episode\nwith a duration (T90) of about 1.3 s (50-300 keV).\nThe time-averaged spectrum from T0-0.32 s to T0+1.15 s is\nbest fit by a power law function with an exponential\nhigh-energy cutoff. The power law index is -0.80 +/- 0.08 and\nthe cutoff energy, parameterized as Epeak, is 1.2 +/- 0.3 MeV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(2.04 +/- 0.08)E-06 erg/cm^2. The 64-ms peak photon flux measured\nstarting from T0+0.32 s in the 10-1000 keV band\nis 11.1 +/- 1.1 ph/s/cm^2.\n\n\nThe spectral analysis results presented above are preliminary; \nfinal results will be published in the GBM GRB Catalog: \nhttps://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html\n \nFor Fermi GBM data and info, please visit the official Fermi GBM Support Page: \nhttps://fermi.gsfc.nasa.gov/ssc/data/access/gbm/\"",
  "eventId": "GRB 251117A",
  "subject": "GRB 251117A: Fermi GBM observation",
  "createdOn": 1763481037921,
  "bibcode": "2025GCN.42737....1B",
  "circularId": 42737
}