{
  "bibcode": "2008GCN..8182....1S",
  "body": "M. C. Stroh (PSU), S. D. Barthelmy (GSFC),\nW. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester),\nD. N. Burrows (PSU), M. M. Chester (PSU), J. R. Cummings (NASA/UMBC),\nP. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),\nS. T. Holland (CRESST/USRA/GSFC), S. Immler (CRESST/GSFC/UMD),\nJ. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA),\nF. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester),\nC. Pagani (PSU), K. L. Page (U Leicester), B. Preger (ASDC),\nJ. L. Racusin (PSU), T. Sakamoto (NASA/UMBC), P. Schady (MSSL-UCL),\nR. L. C. Starling (U Leicester) and L. Vetere (PSU) report on behalf\nof the Swift Team:\n\nAt 16:55:45 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 080905B (trigger=323898).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 301.723, -62.571 which is \n   RA(J2000) = 20h 06m 53s\n   Dec(J2000) = -62d 34' 15\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve showed three well separated\npeaks each about 10 seconds long with a total burst duration of about \n90 sec.  The peak count rate was ~2000 counts/sec (15-350 keV), at ~4 sec \nafter the trigger. \n\nThe XRT began observing the field at 16:57:28.6 UT, 103.2 seconds after\nthe BAT trigger. Using promptly downlinked data we find a bright,\nuncatalogued X-ray source with an enhanced position: RA, Dec 301.74027,\n-62.56347 which is equivalent to:\n   RA(J2000)  = 20h 06m 57.66s\n   Dec(J2000) = -62d 33' 48.5\"\nwith an uncertainty of 2.7 arcseconds (radius, 90% containment). This\nlocation is 39 arcseconds from the BAT onboard position, within the BAT\nerror circle. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density in excess of the Galactic value (3.49e+20\ncm^-2, Kalberla et al. 2005), with an excess column of 1.7\n(+1.47/-1.31) x 10^21 cm^-2 (90% confidence). \n\nThe initial flux in the 2.5 s image was 2.11e-09 erg cm^-2 s^-1 (0.2-10\nkeV). \n\nUVOT took a finding chart exposure of 100 seconds with the White   \n(160-650 nm)  filter starting 112 seconds after the BAT trigger.   \nThe 2.7'x2.7' sub-image covers 100% of the XRT error circle.  Inside \nthe XRT error circle is a 16th mag source that is starlike in the DSS,\n  but appears  extended or double in the UVOT image and may be an  \noptical afterglow.  A second finding chart in V does not allow us to \n confirm or reject the candidate at this time.  No  correction has  \nbeen made for the  expected extinction corresponding to E(B-V) of   \n0.05. \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": 8182,
  "createdOn": 1220635323000,
  "email": "kennea@astro.psu.edu",
  "subject": "GRB 080905B: Swift detection of a burst with possible optical counterpart",
  "submitter": "Jamie A. Kennea at PSU/Swift-XRT  <kennea@astro.psu.edu>",
  "eventId": "GRB 080905B"
}