{
  "bibcode": "2021GCN.29602....1O",
  "body": "M. Ohno (Hiroshima Univ. & Eotvos Univ.), M. Axelsson (KTH &\nStockholmUniv.), S. Cutini (INFN Perugia), F. Longo (University & INFN\nTrieste), and M. Crnogorcevic (Univ. of Maryland & NASA/GSFC)\nreport on behalf of the Fermi-LAT Collaboration:\n\nOn March 06, 2021, Fermi-LAT detected high-energy emission from GRB\n210306A, which was also detected by\nFermi-GBM (trigger 636695642), Swift (D'Elia et al.; GCN 29597), and\nconfirmed the afterglow by ground telescopes\n(M. Watson et al.; GCN 29598, Dmitrievich Romanov; GCN 29599,\nStrausbaugh and. Cucchiara; GCN 29600).\n\nThe best LAT on-ground location is found to be RA, Dec 130.3, 60.2\n(degrees, J2000)\nwith an error radius of 0.38 deg (90% containment, statistical error only).\nThis was 10 deg from the LAT boresight at the time of the GBM trigger:\n\nT0 =  03:53:57.11 UT.\n\nThe data from the Fermi-LAT show a significant increase\nin the event rate after the GBM trigger that is spatially correlated with the\nGBM emission (5.8 degrees from the GBM location) with high significance.\nThe photon flux above 100 MeV in the time interval 0-3000 s after the\nGBM trigger is (6.6+/-3.5 e-7) ph/cm2/s.\n\nThe estimated photon index above 100 MeV is -2.0(+/-0.4).\n\nThe highest-energy photon is a 1.9 GeV event which is observed 790 seconds\nafter the GBM trigger.\n\nThe Fermi-LAT point of contact for this burst is\nMilena Crnogorcevic (mcrnogor@astro.umd.edu).\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": 29602,
  "createdOn": 1615040342000,
  "email": "milenaGCN@gmail.com",
  "subject": "GRB 210306A: Fermi-LAT detection",
  "submitter": "Milena Crnogorcevic at U.of Maryland/NASA-GSFC  <milenaGCN@gmail.com>",
  "eventId": "GRB 210306A"
}