{
  "bibcode": "2015GCN.17799....1M",
  "body": "A. Maselli (INAF-IASFPA), S. D. Barthelmy (GSFC),\nJ. R. Cummings (NASA/UMBC), N. Gehrels (NASA/GSFC),\nJ. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL),\nF. E. Marshall (NASA/GSFC), K. L. Page (U Leicester) and\nM. H. Siegel (PSU) report on behalf of the Swift Team:\n\nAt 11:30:42 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated a possible GRB (trigger=639636).  Swift slewed immediately\nto the location.  The BAT on-board calculated location is \nRA, Dec 350.788, +7.897, which is \n   RA(J2000)  =  23h 23m 09s\n   Dec(J2000) = +07d 53' 50\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  As is typical for image triggers (7.4 sigma),\nthere is nothing significant in the real-time light curve. \n\nThe XRT began observing the field at 11:33:13.7 UT, 151.3 seconds after\nthe BAT trigger. No source was detected in the 2.5-s promptly available\nimage. We are waiting for the full dataset to detect and localise the\nXRT counterpart. \n\nUVOT took a finding chart exposure of 104 seconds with the White filter\nstarting 502 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 16% 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\n0.11. \n\nBurst Advocate for this burst is A. Maselli (maselli AT ifc.inaf.it). \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": 17799,
  "createdOn": 1430567463000,
  "email": "scott@milkyway.gsfc.nasa.gov",
  "subject": "Swift Trigger 639636: a possible GRB",
  "submitter": "Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>"
}