{
  "eventId": "GRB 230818A",
  "submitter": "Cori Fletcher at USRA <cfletcher@usra.edu>",
  "bibcode": "2023GCN.34501....1V",
  "body": "P. Veres (UAH), C. Fletcher (USRA) and C. Meegan (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 23:27:35.37 UT on 18 August 2023, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 230818A (trigger 714094060/230818977).\nwhich was also detected by Swift-BAT (A. Tohuvavohu et al. 2023, GCN 34479) and AstroSat (B. Pari et al. 2023, GCN 34492).\nThe Fermi GBM Final Real-time Localization (GCN 34478) is consistent with the Swift-BAT position.\n\nThe angle from the Fermi LAT boresight is 79 degrees.\n\nThe GBM light curve consists of a couple peaks with a duration (T90)\nof about 10 s (50-300 keV). The time-averaged spectrum\nfrom T0-1.5 to T0+13.8 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -1.02 +/- 0.06 and the cutoff energy,\nparameterized as Epeak, is 260 +/- 30 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(5.6 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+0.58 s in the 10-1000 keV band is 10.2 +/- 0.3 ph/s/cm^2.\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/\"",
  "circularId": 34501,
  "createdOn": 1692556034207,
  "subject": "GRB 230818A: Fermi GBM Observation",
  "submittedHow": "web"
}