{
  "bibcode": "2021GCN.30687....1O",
  "body": "M. Ohno (Eotvos U./Hiroshima U.), D. Kocevski (NASA/MSFC), F. Longo\n(University and INFN, Trieste), a F. Dirirsa (LAPP, Annecy)\nreport on behalf of the Fermi-LAT Collaboration:\n\nOn August 22th, 2021, Fermi-LAT detected high-energy emission from\nGRB 210822A, which was also detected by Swift-BAT (trigger1069788; Page et\nal. GCN Circ. 30677) and GECAM (Wang et al., GCN Circ. 30678).\n\n\nThe best LAT on-ground location is found to be\n\nRA, Dec 304.6, 4.9 (degrees, J2000)\n\nwith an error radius of 0.5 deg (90% containment, statistical error only).\nThis was 83 deg from the LAT boresight at the time of the Swift trigger:\n\nT0 = 09:18:18 UT.\n\nAnd the burst came into the LAT boresight about 500 s after the Swift\ntrigger time.\nThe data from the Fermi-LAT show a significant increase\nin the event rate after the Swift trigger that is spatially correlated with\nthe Swift emission with high significance.\nThe photon flux above 100 MeV in the time interval 500-10000 s after the\nSwift trigger is 2.5(-/+ 0.8)  ph/cm2/s.\n\nThe estimated photon index above 100 MeV is -2.4 (-/+ 0.3).\n\nThe highest-energy photon is a 1.0 GeV event which is observed 855 seconds\nafter the Swift trigger.\n\nThe Fermi-LAT point of contact for this burst is\nFeraol F. Dirirsa (dirirsa@lapp.in2p3.fr ).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover\nthe energy band from 20 MeV to greater than 300 GeV.\nIt is the product of an international collaboration between\nNASA and DOE in the U.S. and many scientific institutions\nacross France, Italy, Japan and Sweden.",
  "circularId": 30687,
  "createdOn": 1629662527000,
  "email": "ohno@astro.hiroshima-u.ac.jp",
  "subject": "GRB 210822A: Fermi-LAT detection",
  "submitter": "Masanori Ohno at Hiroshima U  <ohno@astro.hiroshima-u.ac.jp>",
  "eventId": "GRB 210822A"
}