{
  "bibcode": "2019GCN.26598....1F",
  "body": "F. Fana Dirirsa (Univ. of Johannesburg), F. Longo (University & INFN,\nTrieste), M. Axelsson (KTH & Stockholm Univ.),\nD. Kocevski (NASA/MSFC) and J. Racusin (NASA/GSFC) report on behalf of\nthe Fermi-LAT team:\n\nOn December 27, 2019, Fermi-LAT marginally detected high-energy emission from\nGRB 191227A, which was also detected by Fermi-GBM (GCN 26593) and\nSwift/BAT (Melandri et al, GCN 26595).\nThe best LAT on-ground location is found to be\n\nRA, Dec 318.0, -16.9 (degrees, J2000)\n\nwith an error radius of 0.33 deg (90% containment, statistical error only).\n\nThis was 96 deg from the LAT boresight at the time of the GBM trigger\nand entered in the LAT field of view around\n1 ks later. The localisation is consistent with the Swift/BAT position.\n\nThe detection significance lies just below the 5-sigma threshold, but\nmore than 3 photons with >90% probability to\nbe associated with the GRB are found in the time interval up to 10ks\nafter the GBM trigger. The photon flux above\n100 MeV in this time interval is (9 +/- 4) e-7 ph/cm2/s.\n\nThe estimated photon index above 100 MeV is -2.0 +/- 0.3.\n\nFurther analysis is ongoing.\n\nThe Fermi-LAT point of contact for this burst is Feraol Fana Dirirsa\n(fdirirsa@uj.ac.za)\n\nThe Fermi-LAT is a pair conversion telescope designed to cover the\nenergy band from 20 MeV to greater than 300 GeV.\nIt is the product of an international collaboration between NASA and\nDOE in the U.S. and many scientific institutions\nacross France, Italy, Japan and Sweden.",
  "circularId": 26598,
  "createdOn": 1577466942000,
  "email": "franzlongo1969@gmail.com",
  "subject": "GRB 191227A: Marginal detection by Fermi-LAT",
  "submitter": "Francesco Longo at U of Trieste,INFN Trieste  <franzlongo1969@gmail.com>",
  "eventId": "GRB 191227A"
}