TITLE: GCN CIRCULAR NUMBER: 13659 SUBJECT: GRB 120816A: Swift-BAT refined analysis DATE: 12/08/17 02:28:16 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), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), 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+192 sec from the recent telemetry downlink, we report further analysis of BAT GRB 120816A (trigger #531223) (Page, et al., GCN Circ. 13654). The BAT ground-calculated position is RA, Dec = 282.133, -6.981 deg, which is RA(J2000) = 18h 48m 32.0s Dec(J2000) = -06d 58' 51.6" with an uncertainty of 2.5 arcmin, (radius, sys+stat, 90% containment). The partial coding was 9%. The mask-weighted light curve shows a single peak starting at ~T+0 sec, peaking at ~T+1 sec, and ending at ~T+8 sec. T90 (15-350 keV) is 7.6 +- 3.1 sec (estimated error including systematics). The time-averaged spectrum from T-1.97 to T+6.66 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.54 +- 0.40. The fluence in the 15-150 keV band is 4.3 +- 1.0 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.82 sec in the 15-150 keV band is 2.1 +- 0.5 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/531223/BA/