{
  "bibcode": "2008GCN..8021....1I",
  "body": "S. Immler (CRESST/GSFC/UMD), W. H. Baumgartner (GSFC/UMBC),\nN. Gehrels (NASA/GSFC), S. D. Hunsberger (PSU), W.B Landsman (GSFC),\nC. B. Markwardt (CRESST/GSFC/UMD), K. L. Page (U Leicester),\nD. M. Palmer (LANL), A. M. Parsons (GSFC), D. Perez (U Leicester),\nT. Sakamoto (NASA/UMBC) and T. N. Ukwatta (GSFC/GWU) report on behalf\nof the Swift Team:\n\nAt 05:57:39 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 080727 (trigger=318094).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 208.389, -18.549 which is \n   RA(J2000) = 13h 53m 33s\n   Dec(J2000) = -18d 32' 55\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve showed a single peak\nstructure with a duration of about 5 sec.  The peak count rate\nwas ~700 counts/sec (15-350 keV), at ~2 sec after the trigger. \n\nThe XRT began observing the field at 05:59:28.5 UT, 109.2 seconds after\nthe BAT trigger. Using promptly downlinked data we find a fading,\nuncatalogued X-ray source with an enhanced position: RA, Dec 208.39099,\n-18.54505 which is equivalent to:\n   RA(J2000)  = 13h 53m 33.84s\n   Dec(J2000) = -18d 32' 42.2\"\nwith an uncertainty of 2.7 arcseconds (radius, 90% containment). This\nlocation is 15 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 consistent with the Galactic value of\n6.75e+20 cm^-2 (Kalberla et al. 2005). \n\nUVOT took a finding chart exposure of 100 seconds with the White\n(160-650 nm)  filter starting 114 seconds after the BAT trigger. No\nafterglow candidate has  been found in the initial data products. The\n2.7'x2.7' sub-image covers 25% of  the BAT error circle and 100% of\nthe XRT error circle. The typical 3-sigma upper limit has been about \n18.5 mag. The list of sources is typically complete to about 18 mag. \nNo  correction has been made for the expected extinction corresponding \nto E(B-V) of 0.07. \n\nBurst Advocate for this burst is S. Immler (immler 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": 8021,
  "createdOn": 1217139406000,
  "email": "palmer@lanl.gov",
  "subject": "GRB 080727: Swift detection of a burst",
  "submitter": "David Palmer at LANL  <palmer@lanl.gov>",
  "eventId": "GRB 080727"
}