{
  "bibcode": "2008GCN..7685....1B",
  "body": "W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU),\nM. M. Chester (PSU), G. Cusumano (INAF-IASFPA),\nP. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),\nC. Guidorzi (INAF-OAB), S. T. Holland (CRESST/USRA/GSFC),\nS. Immler (CRESST/GSFC/UMD), J. A. Kennea (PSU),\nV. La Parola (INAF-IASFPA), V. Mangano (INAF-IASFPA),\nF. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester),\nC. Pagani (PSU), P. Romano (INAF-IASFPA), T. Sakamoto (NASA/UMBC),\nM. Stamatikos (NASA/ORAU), T. N. Ukwatta (GSFC/GWU) and\nH. Ziaeepour (UCL-MSSL) report on behalf of the Swift Team:\n\nAt 17:46:21 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 080506 (trigger=311159).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 329.435, +39.002 which is \n   RA(J2000) = 21h 57m 44s\n   Dec(J2000) = +39d 00' 08\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  As this is an image trigger, the BAT light curve does \nnot show meaningful emission from the burst. \n\nThe XRT began observing the field at 17:48:41.3 UT, 140.1 seconds after\nthe BAT trigger. Using promptly downlinked data we find a bright,\nuncatalogued X-ray source located at RA, Dec 329.42145, 38.98413 which\nis equivalent to:\n   RA(J2000)  = 21h 57m 41.15s\n   Dec(J2000) = +38d 59' 02.9\"\nwith an uncertainty of 3.3 arcseconds (radius, 90% containment). This\nlocation is 74 arcseconds from the BAT onboard position, within the BAT\nerror circle. The XRT light curve from TDRSS data is fading. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata does not constrain the column density, so we cannot provide limits\non the redshift using spectroscopy and the relation from Grupe et al. \n(2007). A summary of the promptly downlinked data is given at\nhttp://www.swift.ac.uk/sper/311159/. \n\nThe initial flux in the 2.5 s image was 5.50e-09 erg cm^-2 s^-1 (0.2-10\nkeV). \n\n\nUVOT took a finding chart exposure of 400 seconds with the V filter starting\n143 seconds after the BAT trigger. There is a candidate afterglow in the\nrapidly available 2.7'x2.7' sub-image at\n  RA(J2000)  =\t21:57:41.83 = 329.4243\n  DEC(J2000) = +38:59:06.4  =  38.9851\nwith a 1-sigma error radius of about 0.5 arc sec. This position is 8.0 arc sec. \nfrom the center of the XRT error circle. The estimated magnitude is 18.3 with a\n1-sigma error of about 0.5 mag. No correction has been made for the expected\nextinction of about 0.8 magnitudes. \n\nBurst Advocate for this burst is W. H. Baumgartner (wayne AT milkyway.gsfc.nasa.gov). \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": 7685,
  "createdOn": 1210097187000,
  "email": "wayne@milkyway.gsfc.nasa.gov",
  "subject": "GRB 080506: Swift detection of a burst with optical afterglow",
  "submitter": "Wayne Baumgartner at GSFC  <wayne@milkyway.gsfc.nasa.gov>",
  "eventId": "GRB 080506"
}