TITLE: GCN CIRCULAR NUMBER: 13022 SUBJECT: GRB 120308A: Swift-BAT refined analysis DATE: 12/03/08 13:50:31 GMT FROM: Scott Barthelmy at NASA/GSFC T. Sakamoto (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), M. Stamatikos (OSU), G. Sato (ISAS), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+962 sec from recent telemetry downlinks, we report further analysis of BAT GRB 120308A (trigger #517234) (Baumgartner, et al., GCN Circ. 13017). The BAT ground-calculated position is RA, Dec = 219.123, 79.674 deg, which is RA(J2000) = 14h 36m 29.5s Dec(J2000) = +79d 40' 25.7" with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 97%. The mask-weighted light curve shows a mostly smooth peak starting at ~T-30 sec, peaking at ~T+1 sec, and ending at ~T+70 sec. T90 (15-350 keV) is 60.6 +- 17.1 sec (estimated error including systematics). The time-averaged spectrum from T-24.15 to T+58.20 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.71 +- 0.13. The fluence in the 15-150 keV band is 1.2 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+0.62 sec in the 15-150 keV band is 0.6 +- 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/517234/BA/