{
  "bibcode": "2022GCN.32212....1D",
  "body": "N. Di Lalla (Stanford Univ.), M. Arimoto (Kanazawa Univ.), M. Axelsson \n(KTH & Stockholm Univ.) and\nG. Principe (University and INFN Trieste) report on behalf of the \nFermi-LAT team:\n\nOn June 17, 2022, Fermi-LAT detected high-energy emission from GRB 220617A,\nwhich was also detected by��Fermi-GBM (trigger��677183477 / 220617772, GCN \n32209).\n\nThe best LAT on-ground location is found to be\n\nRA, Dec = 156.96, 15.53 (degrees, J2000)\n\nwith an error radius of 0.09 deg (90 % containment, statistical error \nonly).\nThis was 46 deg from the LAT boresight at the time of the GBM trigger:\n\nT0 =��18:31:12 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 \nhigh significance.\nThe photon flux above 100 MeV in the time interval 0-200 s\nafter the GBM trigger is (4.9 +/- 0.8)E-05 ph/cm2/s.\n\nThe estimated photon index above 100 MeV is -1.9 +/- 0.1.\n\nThe highest-energy photon is a 8.2 GeV event which is observed 0.9 \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 Giacomo Principe \n(giacomo.principe@ts.infn.it <mailto:giacomo.principe@ts.infn.it>).\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the \nenergy band\nfrom 20 MeV to greater than 300 GeV. It is the product of an international\ncollaboration between NASA and DOE in the U.S. and many scientific \ninstitutions\nacross France, Italy, Japan and Sweden.",
  "circularId": 32212,
  "createdOn": 1655517428000,
  "email": "niccolo.dilalla@stanford.edu",
  "subject": "GRB 220617A: Fermi-LAT detection",
  "submitter": "Niccolo Di Lalla at Stanford U  <niccolo.dilalla@stanford.edu>",
  "eventId": "GRB 220617A"
}