{
  "submittedHow": "web",
  "eventId": "GRB 250920A",
  "circularId": 41918,
  "subject": "GRB 250920A: Fermi GBM Detection",
  "format": "text/plain",
  "submitter": "Rushikesh Digambar Sonawane PHD231014 at IISER, TVM <rushikesh23@iisertvm.ac.in>",
  "bibcode": "2025GCN.41918....1S",
  "body": "R. Sonawane (IISER, TVM) and J.R. Smith (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 02:54:06.82 UT on 20 September 2025, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 250920A (trigger 780029651/250920121).\nwhich was also detected by AstroSat-CZTI( Harsha K. H. et al. 2025, GCN 41899), and \nSVOM-GRM (Chen-Wei Wang et al. 2025, GCN 41912).\n\nThe Fermi GBM Final Localization is presented in GCN 41895.\n\nThe angle from the Fermi LAT boresight is 88 degrees.\n\nThe GBM light curve consists of two emission episodes with a duration (T90)\nof about 9.4 s (50-300 keV). The time-averaged spectrum\nfrom T0+0.003 to T0+13.312 s is best fit by\na Band function with Epeak = 151 +/- 3 keV,\nalpha = -0.81 +/- 0.02, and beta = -2.39 +/- 0.04.\n\nThe event fluence (10-1000 keV) in this time interval is\n(4.22 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+1.7 s in the 10-1000 keV band is 102.5 +/- 0.7 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/\"",
  "createdOn": 1758402078838
}