{
  "bibcode": "2017GCN.21039....1L",
  "body": "A. Y. Lien (GSFC/UMBC), K. L. Page (U Leicester) and\nD. M. Palmer (LANL) report on behalf of the Swift Team:\n\nAt 22:44:21 UT, the Swift Burst Alert Telescope (BAT) detected an \nimage peak in the vicinity of a nearby galaxy (trigger=750096).  \nSwift slewed immediately to the location. \nThe BAT on-board calculated location is \nRA, Dec 184.880, +5.656 which is \n   RA(J2000) = 12h 19m 31s\n   Dec(J2000) = +05d 39' 21\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve shows no significant \nactivity. \n\nThe XRT began observing the field at 22:46:18.1 UT, 117.1 seconds after\nthe BAT trigger. No source was detected in 513 s of promptly downlinked\ndata. \n\nUVOT took a finding chart exposure of 250 seconds with the U filter starting\n117 seconds after the BAT trigger. No credible afterglow candidate has been\nfound in the initial data products. The 2.7'x2.7' sub-image processing FAILED\nbecause of no aspect solution. Results from the list of sources generated\non-board are not available at this time. No correction has been made for the\nexpected extinction corresponding to E(B-V) of 0.02. \n\nDue to the low significance of the image peak (5.80 sigma), the \nlarge distance to the potential associated source (7.7 arcminutes),\nthe lack of activity in the BAT count rates, and the non-detection \nby XRT, we believe that this is merely a noise fluctuation in\nthe image plane and not an astrophysical source. \n\nThis trigger, like the earlier Trigger #750044, was the result\nof a triggering strategy that locally depresses the threshold \nsignificance in the vicinity of known sources and nearby galaxies \nin order to gain greater sensitivity to such sources (at the\nexpense of a higher proportion of false triggers).",
  "circularId": 21039,
  "createdOn": 1493247626000,
  "email": "palmer@lanl.gov",
  "subject": "Swift Trigger 750096 is probably a noise fluctuation",
  "submitter": "David Palmer at LANL  <palmer@lanl.gov>"
}