{
  "bibcode": "2008GCN..8691....1G",
  "body": "D. Grupe (PSU), M. M. Chester (PSU), J. R. Cummings (NASA/UMBC),\nN. Gehrels (NASA/GSFC), C. B. Markwardt (CRESST/GSFC/UMD),\nD. M. Palmer (LANL), J. L. Racusin (PSU), M. Stamatikos (NASA/ORAU)\nand M. C. Stroh (PSU) report on behalf of the Swift Team:\n\nAt 04:53:59 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 081222 (trigger=337914).  Swift slewed immediately to the \nburst.  The BAT on-board calculated location is \nRA, Dec 22.751, -34.128 which is \n   RA(J2000) = 01h 31m 00s\n   Dec(J2000) = -34d 07' 41\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve showed a multipeaked\nstructure with a duration of about 20 sec.  The peak count rate\nwas ~10000 counts/sec (15-350 keV), at 3 sec after the trigger. \n\nThe XRT began observing the field at 04:54:51.7 UT, 51.8 seconds after\nthe BAT trigger. Using promptly downlinked data we find a bright, fading,\nuncatalogued X-ray source located at RA, Dec 22.74067, -34.09556 which\nis equivalent to:\n   RA(J2000)  = 01h 30m 57.76s\n   Dec(J2000) = -34d 05' 44.0\"\nwith an uncertainty of 3.6 arcseconds (radius, 90% containment). This\nlocation is 120 arcseconds from the BAT onboard position, within the\nBAT error circle. This position may be improved as more data are\nreceived; the latest position is available at\nhttp://www.swift.ac.uk/sper. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density consistent with the Galactic value of\n2.24e+20 cm^-2 (Kalberla et al. 2005). \n\nThe initial flux in the 2.5 s image was 3.91e-09 erg cm^-2 s^-1 (0.2-10\nkeV). \n\nUVOT took a finding chart exposure of 150 seconds with the White\nfilter  starting 60 seconds after the BAT trigger. There is a\ncandidate afterglow in  the rapidly available 2.7'x2.7' sub-image\nconsistent with the XRT candidate.  A precise location and magnitude\nestimate are not available at this time. \n\nThis burst is consistent with the Fermi GBM burst   Trigger 251614441. \n\nBurst Advocate for this burst is D. Grupe (grupe AT astro.psu.edu). \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": 8691,
  "createdOn": 1229923703000,
  "email": "palmer@lanl.gov",
  "subject": "GRB 081222: Swift detection of a burst with a bright optical afterglow",
  "submitter": "David Palmer at LANL  <palmer@lanl.gov>",
  "eventId": "GRB 081222"
}