TITLE: GCN CIRCULAR NUMBER: 14068 SUBJECT: GRB 121212A: Swift-BAT refined analysis DATE: 12/12/12 13:47:49 GMT FROM: Scott Barthelmy at NASA/GSFC S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), D. Grupe (PSU), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team): Using the data set from T-60 to T+243 sec from recent telemetry downlinks, we report further analysis of BAT GRB 121212A (trigger #541371) (Grupe, et al., GCN Circ. 14064). The BAT ground-calculated position is RA, Dec = 177.787, 78.052 deg, which is RA(J2000) = 11h 51m 08.8s Dec(J2000) = +78d 03' 05.4" with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%. The mask-weighted light curve shows a couple peaks starting at ~T-3 sec, peaking at ~T+0 sec, and ending at ~T+16 sec. T90 (15-350 keV) is 6.8 +- 1.3 sec (estimated error including systematics). The time-averaged spectrum from T+0.02 to T+7.84 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.65 +- 0.40. The fluence in the 15-150 keV band is 1.2 +- 0.3 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.02 sec in the 15-150 keV band is 0.7 +- 0.1 ph/cm2/sec. All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/541371/BA/