{
  "bibcode": "2024GCN.38231....1D",
  "eventId": "LIGO/Virgo/KAGRA S241114bi",
  "circularId": 38231,
  "format": "text/plain",
  "body": "S. Dalessi (UAH) reports on behalf of the Fermi-GBM Team:\n\n\nFor S241114bi (GCN 38228) and using the initial bayestar skymap, Fermi-GBM was observing 59.4% of the localization probability at event time.\n\nThere was no Fermi-GBM onboard trigger around the event time of the LIGO/Virgo/KAGRA (LVK) detection of GW trigger S241114bi. An automated, blind search for short gamma-ray bursts below the onboard triggering threshold in Fermi-GBM also identified no counterpart candidates. The GBM targeted search, the most sensitive, coherent search for GRB-like signals, was run from +/-30 s around merger time, and also identified no counterpart candidates.\n\nPart of the LVK localization region is behind the Earth for Fermi, located at an RA=63.3, Dec=4.0 with a radius of 68.0 degrees. We therefore set upper limits on impulsive gamma-ray emission for the GW localization region visible to Fermi at merger time. Using the representative soft, normal, and hard GRB-like templates described in arXiv:1612.02395, we set the following 3 sigma flux upper limits over 10-1000 keV, weighted by GW localization probability (in units of 10^-7 erg/s/cm^2):\n\nTimescale  Soft   Normal   Hard \n------------------------------------\n0.128 s:    1.2        2.0       3.7\n1.024 s:    0.42       0.66      1.2\n8.192 s:    0.13       0.18      0.22\n\nAssuming the median luminosity distance of 781.7 Mpc from the GW detection, we estimate the following intrinsic luminosity upper limits over the 1 keV-10 MeV energy range (in units of 10^50 erg/s):\n\nTimescale  Soft    Normal   Hard \n------------------------------------\n0.128s: \t  0.14     0.21       0.63\n1.024s: \t  0.047    0.068      0.20\n8.192s:           0.015    0.019      0.038",
  "createdOn": 1731647610721,
  "subject": "LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations",
  "submitter": "Sarah Dalessi at UAH <sd0104@uah.edu>",
  "submittedHow": "web"
}