{
  "bibcode": "2020GCN.26916....1W",
  "body": "J. Wood (NASA/MSFC) reports on behalf of the Fermi-GBM Team and the\nGBM-LIGO/Virgo group\n\nFor S200128d and using the bayestar.fits.gz,1 skymap, Fermi-GBM was observing\n48.7% of the localization probability at event time.\n\nThere was no Fermi-GBM onboard trigger around the event time of the\nLIGO/Virgo detection of GW trigger S200128d (GCN 26906). An\nautomated, blind search for short gamma-ray bursts below the onboard\ntriggering threshold in Fermi-GBM also identified no counterpart\ncandidates. The GBM targeted search, the most sensitive, coherent search\nfor GRB-like signals, was run from +/-30 s around merger time, and also\nidentified no counterpart candidates.\n\nPart of the LVC localization region is behind the Earth for Fermi, located\nat RA=266.6, Dec=-24.9 with a radius of 67.5 degrees. We therefore set upper\nlimits on impulsive gamma-ray emission for the LVC localization region\nvisible to Fermi at merger time. Using the representative soft, normal, and\nhard GRB-like templates described in arXiv:1612.02395, we set the following\n3 sigma flux upper limits over 10-1000 keV, weighted by GW localization\nprobability (in units of 10^-7 erg/s/cm^2):\n\nTimescale   Soft   Normal   Hard\n------------------------------------\n0.128 s:    2.5    3.2      8.3\n1.024 s:    0.8    1.3      2.7\n8.192 s:    0.2    0.4      1.0\n\nAssuming the median luminosity distance of 4031 Mpc from the GW detection,\nwe estimate the following intrinsic luminosity upper limits over the 1\nkeV-10 MeV energy range (in units of 10^50 erg/s):\n\nTimescale   Soft   Normal   Hard\n------------------------------------\n0.128s:     7.8    8.5      37.\n1.024s:     2.4    3.4      12.\n8.192s:     0.7    1.0      4.5",
  "circularId": 26916,
  "createdOn": 1580221310000,
  "email": "joshua.r.wood@nasa.gov",
  "subject": "LIGO/Virgo S200128d: Upper limits from Fermi-GBM Observations",
  "submitter": "Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood@nasa.gov>",
  "eventId": "LIGO/Virgo S200128d"
}