TITLE: GCN CIRCULAR NUMBER: 13581 SUBJECT: GRB 120804A: Swift-BAT refined analysis DATE: 12/08/04 13:20:44 GMT FROM: Scott Barthelmy at NASA/GSFC W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/GSFC/ORAU), C. B. Markwardt (GSFC), 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-240 to T+962 sec from recent telemetry downlinks, we report further analysis of BAT GRB 120804A (trigger #529686) (Lien, et al., GCN Circ. 13573). The BAT ground-calculated position is RA, Dec = 233.951, -28.768 deg, which is RA(J2000) = 15h 35m 48.1s Dec(J2000) = -28d 46' 06.1" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 24%. The mask-weighted light curve shows two overlapping peaks starting at ~T-0.2 sec, peaking at ~T+0.1 and ~T+0.5 sec, and ending at ~T+1.0 sec. T90 (15-350 keV) is 0.81 +- 0.08 sec (estimated error including systematics). The time-averaged spectrum from T-0.16 to T+0.83 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.34 +- 0.08. The fluence in the 15-150 keV band is 8.8 +- 0.5 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.16 sec in the 15-150 keV band is 10.8 +- 0.6 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/529686/BA/