{
  "bibcode": "2020GCN.27291....1D",
  "body": "N. Di Lalla (Stanford Univ.), F. Longo (University and INFN, Trieste),\nD. Kocevski (NASA/MSFC),\nN. Omodei (Stanford Univ.), M. Arimoto (Kanazawa Univ.), A. Berretta\n(University & INFN Perugia),\nM. Crnogorcevic (Univ. of Maryland & NASA/GSFC), M. Axelsson (KTH &\nStockholm Univ) and\nE. Bissaldi (Politecnico & INFN Bari) report on behalf of the\nFermi-LAT Collaboration:\n\nWe have searched data collected by the Fermi Large Area Telescope (LAT) on\nMarch 2, 2020, for possible high-energy (E > 100 MeV) gamma-ray emission in\nspatial/temporal coincidence with the LIGO/Virgo trigger S200302c (GCN 27278).\n\nWe define \"instantaneous coverage\" as the integral over the region of the LIGO\nprobability map that is within the LAT field of view at a given time,\nand \"cumulative\ncoverage\" as the integral of the instantaneous coverage over time. Fermi-LAT had\nan instantaneous coverage of ~23% of the LIGO probability at the time\nof the trigger\n(T0 = 2020-03-02 01:58:11.519 UTC), and reached 100% cumulative coverage\nafter ~5 ks.\n\nWe performed a search for a transient counterpart within the observed region of\nthe 90% contour of LIGO map in  a fixed time window from T0 to T0 + 10 ks.\nNo significant new sources are found.\n\nA marginally significant excess (with a  soft spectrum) was found at\nthe location\nRA, Dec  63.3, Dec = 18.8 (degrees, J2000)\nwith an error radius of 1.0 deg (90% containment, statistical error only).\n\nWe also performed a search which adapted the time interval of the\nanalysis to the\nexposure of each region of the sky, and no additional excesses were found.\n\nEnergy flux upper bounds for the fixed time interval between 100 MeV and 1 GeV\nfor this search vary between 1.1e-10 and 1.1e-09 [erg/cm^2/s].\n\nThe Fermi-LAT point of contact for this event is\nMakoto Arimoto (arimoto@se.kanazawa-u.ac.jp).\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": 27291,
  "createdOn": 1583199531000,
  "email": "arimoto@hp.phys.titech.ac.jp",
  "subject": "LIGO/Virgo S200302c: No significant counterpart candidates in Fermi-LAT observations",
  "submitter": "Makoto Arimoto at Tokyo Inst of Tech  <arimoto@hp.phys.titech.ac.jp>",
  "eventId": "LIGO/Virgo S200302c"
}