{
  "createdOn": 1706714884371,
  "body": "S. Dalessi (UAH), V Sharma (NASA-GSFC/UMBC) and C. Meegan (UAH) report\non behalf of the Fermi Gamma-ray Burst Monitor Team:\n\n\"At 15:09:22.53 UT on 29 January 2024, the Fermi Gamma-ray Burst Monitor (GBM)\ntriggered and located GRB 240129A (trigger 728233767/240129632), which was also\ndetected by Swift/BAT-GUANO (DeLaunay et al. 2024, GCN 35653).\n\nThe on-ground calculated location, using the Fermi GBM trigger data,\nis RA = 108.02, Dec = 34.60 (J2000 degrees, equivalent to\nJ2000 07h 12m, 34d 36'), with a statistical uncertainty of 3.18 degrees.\n(radius, 1-sigma containment, statistical only; there is additionally a\nsystematic error which we have characterized as a core-plus-tail model,\nwith 90% of GRBs having a 3.7 deg error and a small tail suffering a larger\nthan 10 deg systematic error [Connaughton et al. 2015, ApJS, 216, 32]).\n\nThe angle from the Fermi LAT boresight is 114 degrees.\n\nThe GBM light curve of a single emission episode with a duration (T90)\nof about 28 s (50-300 keV). The time-averaged spectrum\nfrom T0+6.1 to T0+21.5 s is best fit by\na power law function with an exponential high-energy cutoff.\nThe power law index is -1.24 +/- 0.09 and the cutoff energy,\nparameterized as Epeak, is 74 +/- 6 keV.\n\nThe event fluence (10-1000 keV) in this time interval is\n(4.6 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured\nstarting from T0+0.38 s in the 10-1000 keV band is 4.9 +/- 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/.\"",
  "subject": "GRB 240129A: Fermi GBM Observation",
  "bibcode": "2024GCN.35655....1D",
  "circularId": 35655,
  "submittedHow": "web",
  "eventId": "GRB 240129A",
  "submitter": "Vidushi Sharma at NASA GSFC/UMBC <vidushi.sharma@nasa.gov>"
}