{
  "eventId": "GRB 240303B",
  "submittedHow": "web",
  "createdOn": 1709566889953,
  "body": "R. Hamburg (CNRS/IN2P3/IJCLab) and C. Meegan (UAH) report on behalf of\nthe Fermi Gamma-ray Burst Monitor Team:\n\n\"At 12:18:51.24 UT on 03 March 2024, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 240303B (trigger 731161136 / 240303513).\nThe on-ground calculated location is reported in GCN 35850.\nThis burst was also detected by CALET (Nakahira et al., 2024; GCN 35857)\nand the INTEGRAL SPI-ACS (trigger 10612).\n\nThe angle from the Fermi LAT boresight is 96 degrees.\n\nThe GBM light curve consists of a single bright pulse with a duration (T90)\nof about 5.9 s (50-300 keV). The time-averaged spectrum\nfrom T0-1.0 to T0+8.2 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -0.33 +/- 0.03 and the cutoff energy,\nparameterized as Epeak, is 540 +/- 20 keV.\nA Band function fits the spectrum equally well\nwith Epeak= 510 +/- 20 keV, alpha = -0.30 +/- 0.04 and beta = -3 +/- 0.3.\n\nThe event fluence (10-1000 keV) in this time interval is\n(2.31 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+3.9 s in the 10-1000 keV band is 18.5 +/- 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/\"",
  "bibcode": "2024GCN.35860....1H",
  "subject": "GRB 240303B: Fermi GBM Detection",
  "circularId": 35860,
  "submitter": "rachel.hamburg@ijclab.in2p3.fr"
}