{
  "bibcode": "2009GCN.10280....1S",
  "body": "T. Sakamoto (NASA/UMBC), S. D. Barthelmy (GSFC),\nW. H. Baumgartner (GSFC/UMBC), S. Campana (INAF-OAB),\nP. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),\nO. Godet (U Leicester), C. Guidorzi (U Ferrara),\nS. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU),\nW.B Landsman (GSFC), V. Mangano (INAF-IASFPA),\nF. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester),\nK. L. Page (U Leicester), D. M. Palmer (LANL),\nJ. L. Racusin (NASA/GSFC), B. Sbarufatti (INAF-IASFPA),\nG. Stratta (ASDC), M. C. Stroh (PSU), E. Troja (NASA/GSFC/ORAU) and\nT. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:\n\nAt 15:39:06 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated trigger=379449.  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 242.043, +51.395 which is \n   RA(J2000) = 16h 08m 10s\n   Dec(J2000) = +51d 23' 42\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  As is usual for an image trigger, the BAT light \ncurve shows nothing of note. \n\nThe XRT began observing the field at 15:41:31.1 UT, 144.5 seconds after\nthe BAT trigger. No source was detected in the promptly available XRT\ndata. We are waiting for the full dataset to detect and localise the\nXRT counterpart. \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 150 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers 25% of\nthe BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. \nThe 8'x8' region for the list of sources generated on-board covers 100% of the\nBAT error circle. The list of sources is typically complete to about 18 mag. No\ncorrection has been made for the expected extinction corresponding to E(B-V) of\n0.02. \n\nBecause this was an image trigger of marginal significance with no\nobvious variation in the BAT light curve, and because there is no\nsource found in the immediate XRT follow-up, we cannot confirm\nthat this is an actual GRB.  Final determination will require\nanalysis of the data downlinked through Malindi. \n\nBurst Advocate for this burst is T. Sakamoto (Taka.Sakamoto AT 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": 10280,
  "createdOn": 1260893092000,
  "email": "palmer@lanl.gov",
  "subject": "Trigger 379449: Swift detection of a possible burst",
  "submitter": "David Palmer at LANL  <palmer@lanl.gov>"
}