{
  "bibcode": "2012GCN.13780....1B",
  "body": "B. N. Barlow (PSU), W. H. Baumgartner (GSFC/UMBC), V. D'Elia (ASDC),\nN. Gehrels (NASA/GSFC), C. Gronwall (PSU), D. Grupe (PSU),\nE. A. Helder (PSU), J. A. Kennea (PSU) and B.-B. Zhang (PSU) report on\nbehalf of the Swift Team:\n\nAt 11:58:06 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated trigger=534017.  Swift slewed immediately to the trigger location. \nThe BAT on-board calculated location is \nRA, Dec 345.700, -39.715 which is \n   RA(J2000) = 23h 02m 48s\n   Dec(J2000) = -39d 42' 52\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  This event resulted from a 64s image trigger, \nand as usual for these events nothing is seen in the BAT light curve.  This\ntrigger was a sub threshold trigger (5.8 sigma significance), and is \nspatially coincident with a nearby galaxy (11 arc minutes from NGC 7456). \nFurther analysis of data on the ground will be required to verify the \nreality of this event. \n\nThe XRT began observing the field at 12:00:15.4 UT, 129.1 seconds after\nthe BAT trigger. No source was detected in 157 s of promptly downlinked\ndata, which covered 94% of the BAT error circle. We are waiting for the\nfull dataset to detect and localise the XRT counterpart. \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 132 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers 25% of\nthe BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. \nThe 8'x8' region for the list of sources generated on-board covers 100% of the\nBAT error circle. The list of sources is typically complete to about 18 mag. No\ncorrection has been made for the expected extinction corresponding to E(B-V) of\n0.01.",
  "circularId": 13780,
  "createdOn": 1347971119000,
  "email": "caryl@astro.psu.edu",
  "subject": "Swift Trigger 534017 is probably not real.",
  "submitter": "Caryl Gronwall at PSU/Swift-UVOT  <caryl@astro.psu.edu>"
}