{
  "bibcode": "2013GCN.15183....1P",
  "body": "M. J. Page (UCL-MSSL), A. P. Beardmore (U Leicester),\nD. N. Burrows (PSU), N. Gehrels (NASA/GSFC), N. P. M. Kuin (UCL-MSSL),\nF. E. Marshall (NASA/GSFC), C. Pagani (U Leicester),\nK. L. Page (U Leicester), D. M. Palmer (LANL) and\nV. N. Yershov (UCL-MSSL) report on behalf of the Swift Team:\n\nAt 21:41:13 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 130907A (trigger=569992).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 215.877, +45.616 which is \n   RA(J2000) = 14h 23m 31s\n   Dec(J2000) = +45d 36' 58\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve showed a complex multi-peaked\nstructure with a duration of about 120 sec.  The peak count rate\nwas ~60000 counts/sec (15-350 keV), at ~25 sec after the trigger. \n\nThe XRT began observing the field at 21:42:19.3 UT, 66.6 seconds after\nthe BAT trigger. XRT found a bright, uncatalogued X-ray source located\nat RA, Dec 215.8926, 45.6094 which is equivalent to:\n   RA(J2000)  = +14h 23m 34.22s\n   Dec(J2000) = +45d 36' 33.8\"\nwith an uncertainty of 5.0 arcseconds (radius, 90% containment). This\nlocation is 45 arcseconds from the BAT onboard position, within the BAT\nerror circle. No event data are yet available to determine the column\ndensity using X-ray spectroscopy. \n\nThe initial flux in the 0.1 s image was 6.33e-08 erg cm^-2 s^-1 (0.2-10\nkeV). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 74 seconds after the BAT trigger. There is a candidate afterglow in\nthe rapidly available 2.7'x2.7' sub-image at\n  RA(J2000)  =\t14:23:34.03 = 215.89181\n  DEC(J2000) = +45:36:27.1  =  45.60753\nwith a 90%-confidence error radius of about 0.61 arc sec. This position is 7.0\narc sec. from the center of the XRT error circle. The estimated magnitude is\n15.55 with a 1-sigma error of about  0.14. No correction has been made for the\nexpected extinction corresponding to E(B-V) of 0.01. \n\nBurst Advocate for this burst is M. J. Page (m.page AT ucl.ac.uk). \nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/too.html.)",
  "circularId": 15183,
  "createdOn": 1378590811000,
  "email": "palmer@lanl.gov",
  "subject": "GRB 130907A: Swift detection of a burst with an optical counterpart",
  "submitter": "David Palmer at LANL  <palmer@lanl.gov>",
  "eventId": "GRB 130907A"
}