TITLE: GCN CIRCULAR NUMBER: 15092 SUBJECT: GRB 130812A, Swift-BAT refined analysis DATE: 13/08/13 16:12:20 GMT FROM: Takanori Sakamoto at AGU D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), T. Sakamoto (GSFC/UMBC), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team): Using the data set from T-144 to T+431 sec from the recent telemetry downlink, we report further analysis of BAT GRB 130812A (trigger #566228) (D'Elia, et al., GCN Circ. 15088). The BAT ground-calculated position is RA, Dec = 92.387, -13.285 deg which is RA(J2000) = 06h 09m 32.8s Dec(J2000) = -13d 17' 06.6" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 75%. The mask-weighted light curve shows multiple spikes peaking at T0, T0+4 sec and T0+7 sec. T90 (15-350 keV) is 7.6 +- 0.5 sec (estimated error including systematics). The time-averaged spectrum from T-0.3 to T+8.5 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.52 +- 0.11. The fluence in the 15-150 keV band is 5.9 +- 0.3 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.14 sec in the 15-150 keV band is 2.8 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis will be available at http://gcn.gsfc.nasa.gov/notices_s/566228/BA/