{
  "bibcode": "2019GCN.24610....1P",
  "body": "D. M. Palmer (LANL), S. D. Barthelmy (NASA/GSFC),\nA. Y. Lien (GSFC/UMBC), T. Sakamoto (AGU),\nA. A. Breeveld (MSSL-UCL), A. P. Beardmore (U. Leicester),\nD. N. Burrows (PSU), S. Campana (INAF-OAB), S. B. Cenko (NASA/GSFC),\nG. Cusumano (INAF-IASF PA), A. D'Ai (INAF-IASFPA),\nP. D'Avanzo (INAF-OAB), V. D'Elia(ASDC), S. Emery (UCL-MSSL),\nP. A. Evans (U. Leicester), P. Giommi (ASI), C. Gronwall (PSU),\nD. Hartmann (Clemson U.), J. A. Kennea (PSU), H. A. Krimm (NSF),\nN. P. M. Kuin (UCL-MSSL), F. E. Marshall (NASA/GSFC),\nA. Melandri (INAF-OAB), J. A. Nousek (PSU),\nS. R. Oates (Uni. of Warwick), P. T. O'Brien (U. Leicester),\nJ. P. Osborne (U. Leicester), C. Pagani (U. Leicester),\nK. L. Page (U.Leicester), M. Perri (ASDC),\nJ. L. Racusin (NASA/GSFC), B. Sbarufatti (INAF-OAB/PSU),\nM. H. Siegel (PSU), G. Tagliaferri (INAF-OAB), A. Tohuvavohu (PSU),\nE. Troja (NASA/GSFC/UMCP) report on behalf of the Swift team:\n\nWe report the search results in the BAT data within T0 +/- 100 s of the\nLVC event S190519bj (LIGO/VIRGO Collaboration GCN Circ. 24598),\nwhere T0 is the LVC trigger time (2019-05-19T15:35:44.398 UTC).\n\nThe center of the BAT FOV at T0 is\nRA = 99.994 deg,\nDEC = -0.010 deg,\nROLL = 296.994 deg.\nThe BAT Field of View (>10% partial coding) covers 0.00% of the integrated\nLVC localization probability, and 0.00% of the galaxy convolved\nprobability (Evans et al. 2016).\n\nWithin T0 +/- 100 s, no significant detections (signal-to-noise ratio\n>~ 5 sigma) are found in the BAT raw light curves with time bins of 64 ms,\n1 s, and 1.6 s. Also, the larger fluctuation seen in the raw light curve is\nlikely due\nto the proximity to the SAA around that time. Assuming an on-axis (100%\ncoded)\nshort GRB with a typical spectrum in the BAT energy range (i.e., a simple\npower-law model with a power-law index of -1.32, Lien & Sakamoto et al.\n2016),\nthe 5-sigma upper limit in the 1-s binned light curve corresponds to a flux\nupper\nlimit (15-350 keV) of ~ 9.82 x 10^-8 erg/s/cm^2.\n\nNo event data are available at this point.\n\nBAT retains decreased, but significant, sensitivity to rate increases for\ngamma-ray events outside of its FOV. About 88.21% of the integrated LVC\nlocalization probability was outside of the BAT FOV but above the\nEarth's limb from Swift's location, and the corresponding flux upper limits\nfor this region are within roughly an order of magnitude higher than those\nwithin the FOV.\n\nThe results of the BAT analysis are available at\nhttps://swift.gsfc.nasa.gov/results/BATbursts/team_web/S190519bj/web/source.html",
  "circularId": 24610,
  "createdOn": 1558321743000,
  "email": "amy.y.lien@nasa.gov",
  "subject": "LIGO/Virgo S190519bj: Swift/BAT Counterpart Search",
  "submitter": "Amy Lien at GSFC  <amy.y.lien@nasa.gov>",
  "eventId": "LIGO/Virgo S190519bj"
}