{
  "bibcode": "2007GCN..7020....1S",
  "body": "M. C. Stroh (PSU), C. Gronwall (PSU), D. Grupe (PSU),\nS. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),\nH. A. Krimm (GSFC/USRA), C. Pagani (PSU), D. M. Palmer (LANL),\nM. Stamatikos (NASA/ORAU), R. L. C. Starling (U Leicester),\nT. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the\nSwift Team:\n\nAt 01:06:36 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 071031 (trigger=295670).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 6.458, -58.045 which is \n   RA(J2000) = 00h 25m 50s\n   Dec(J2000) = -58d 02' 42\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve showed a single peaked\nstructure with a duration of about 30 sec.  The peak count rate\nwas ~600 counts/sec (15-350 keV), at ~3 sec after the trigger. \n\nThe XRT began observing the field at 01:08:19 UT, 103 seconds after the\nBAT trigger. XRT found a bright, fading, uncatalogued X-ray source\nlocated at RA, Dec 6.4061, -58.0585 which is\n   RA(J2000)  =  00h 25m 37.4s\n   Dec(J2000) = -58d 03' 30.6\"\nwith an uncertainty of 4.7 arcseconds (radius, 90% containment). \nThis location is 110 arcseconds from the BAT on-board position,\nwithin the BAT error circle. The initial flux in the 2.5s image\nwas 5.2e-09 erg/cm2/s (0.2-10 keV). \n\nUVOT took a finding chart exposure of 100 seconds with the White (160-650 nm)\nfilter starting 112 seconds after the BAT trigger. There is a candidate afterglow\nin the rapidly available 2.7'x2.7' sub-image at\n   RA(J2000) =\t00:25:37.27 =\t6.4053\n   DEC(J2000) = -58:03:34.2 = -58.0595\nwith a 1-sigma error radius of about 0.5 arc sec. This position is 3.9 arc sec. \nfrom the center of the XRT error circle. The estimated magnitude is 19.8 with a\n1-sigma error of about 0.5 mag. No correction has been made for the expected\nextinction corresponding to E(B-V) of 0.01. \n\nBurst Advocate for this burst is M. C. Stroh (stroh AT astroh.org). \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": 7020,
  "createdOn": 1193793878000,
  "email": "palmer@lanl.gov",
  "subject": "GRB 071031: Swift detection of a burst with an optical counterpart",
  "submitter": "David Palmer at LANL  <palmer@lanl.gov>",
  "eventId": "GRB 071031"
}