{
  "circularId": 37331,
  "createdOn": 1724896382421,
  "bibcode": "2024GCN.37331....1G",
  "body": "R. Gupta (NASA GSFC), and N. Di Lalla (Stanford University) report on\nbehalf of the Fermi-LAT Collaboration:\n\nOn Aug 28, 2024, Fermi-LAT detected high-energy emission from GRB 240828A,\nwhich was also detected by Fermi-GBM (trigger 746549711 / 240828622, GCN\n37317), and AstroSat CZTI (GCN 37328).\n\nThe best LAT on-ground location is found to be:\n\nRA, Dec = 225.49, 36.64 (J2000)\n\nwith an error radius of 0.30 deg (90 % containment, statistical error only).\n\nThis was 93 deg from the LAT boresight at the time of the GBM trigger: T0 =\n14:55:06 UT.\n\nThe data from the Fermi-LAT show a significant increase in the event rate\nthat is spatially and temporally correlated with the GBM emission with high\nsignificance. The photon flux above 100 MeV in the time interval 3500-6100\ns after the GBM trigger is (8.2 +/- 3.8) E-7 ph/cm2/s. The estimated photon\nindex above 100 MeV is -2.1 +/- 0.4.\n\nThe highest-energy photon is a 1.7 GeV event which is observed ~ 5400\nseconds after the GBM trigger.\n\nA Swift ToO has been approved for this burst.\n\nThe Fermi-LAT point of contact for this burst is Niccolo' Di Lalla (\nniccolo.dilalla@stanford.edu).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the energy\nband from 20 MeV to greater than 300 GeV. It is the product of an\ninternational collaboration between NASA and DOE in the U.S. and many\nscientific institutions across France, Italy, Japan and Sweden.\n",
  "eventId": "GRB 240828A",
  "submitter": "Rahul Gupta at NASA GSFC <rahulbhu.c157@gmail.com>",
  "submittedHow": "email",
  "subject": "GRB 240828A: Fermi-LAT detection"
}