{
  "bibcode": "2012GCN.14064....1G",
  "body": "D. Grupe (PSU), W. H. Baumgartner (GSFC/UMBC),\nC. Guidorzi (U Ferrara), H. A. Krimm (CRESST/GSFC/USRA),\nC. B. Markwardt (NASA/GSFC), K. L. Page (U Leicester),\nD. M. Palmer (LANL) and M. Stamatikos (OSU/NASA/GSFC) report on behalf\nof the Swift Team:\n\nAt 06:56:13 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 121212A (trigger=541371).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 177.841, +78.034 which is \n   RA(J2000) = 11h 51m 22s\n   Dec(J2000) = +78d 02' 04\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve showed a FRED-like\nstructure with a duration of about 20 sec.  The peak count rate\nwas ~2300 counts/sec (15-350 keV), at ~0 sec after the trigger. \n\nThe XRT began observing the field at 06:57:21.7 UT, 68.4 seconds after\nthe BAT trigger. Using promptly downlinked data we find an uncatalogued\nX-ray source located at RA, Dec 177.78252, 78.03720 which is equivalent\nto:\n   RA(J2000)  = 11h 51m 07.80s\n   Dec(J2000) = +78d 02' 13.9\"\nwith an uncertainty of 4.1 arcseconds (radius, 90% containment). This\nlocation is 45 arcseconds from the BAT onboard position, within the BAT\nerror circle. This position may be improved as more data are received;\nthe latest position is available at http://www.swift.ac.uk/sper. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density in excess of the Galactic value (3.67 x\n10^20 cm^-2, Kalberla et al. 2005), with an excess column of 4.2\n(+2.54/-2.19) x 10^21 cm^-2 (90% confidence). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 71 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\n0.07. \n\nBurst Advocate for this burst is D. Grupe (dxg35 AT 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": 14064,
  "createdOn": 1355295959000,
  "email": "palmer@lanl.gov",
  "subject": "GRB 121212A: Swift detection of a burst",
  "submitter": "David Palmer at LANL  <palmer@lanl.gov>",
  "eventId": "GRB 121212A"
}