{
  "bibcode": "2012GCN.14111....1B",
  "body": "W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC),\nJ. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),\nC. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU),\nM. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU)\n(i.e. the Swift-BAT team):\n\nUsing the data set from T-61 to T+111 sec from the recent telemetry downlink,\nwe report further analysis of BAT GRB 121226A (trigger #544027)\n(Krimm, et al., GCN Circ. 14105).  The BAT ground-calculated position is\nRA, Dec = 168.620, -30.413 deg which is\n    RA(J2000)  =  11h 14m 28.7s\n    Dec(J2000) = -30d 24' 47.0\"\nwith an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).\nThe partial coding was 35%.  The mask-weighted light curve shows a single peak\nwith duration approximately 1.5 seconds, with no sign of extended emission.\nT90 (15-350 keV) is 1.00 +- 0.20 sec (estimated error including systematics).\n\nThe time-averaged spectrum from T-0.36 to T+0.80 sec is best fit by a simple\npower-law model.  The power law index of the time-averaged spectrum is\n1.51 +- 0.29.  The fluence in the 15-150 keV band is 1.4 +- 0.2 x 10^-7 erg/cm2.\nThe 1-sec peak photon flux measured from T-0.21 sec in the 15-150 keV band\nis 1.6 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence\nlevel.\n\nWhen plotting GRB 121226A on the T90-hardness diagram (see web link below),\nwe see that it falls within the short-hard region of phase space, with T90 = 1.0 \nsec and Hardness ratio (energy fluence ratio 50-100 keV/25-50 keV) = 1.4.\nTherefore we now suggest that GRB 121226A should be classified as a short-hard \nburst.  We do not have a lag analysis available at this time.\n\nThe results of the batgrbproduct analysis are available at\nhttp://gcn.gsfc.nasa.gov/notices_s/544027/BA/",
  "circularId": 14111,
  "createdOn": 1356618426000,
  "email": "hans.krimm@nasa.gov",
  "subject": "GRB 121226A, Swift-BAT refined analysis",
  "submitter": "Hans Krimm at NASA-GSFC  <hans.krimm@nasa.gov>",
  "eventId": "GRB 121226A"
}