TITLE: GCN CIRCULAR NUMBER: 13220 SUBJECT: GRB 120404A: Swift-BAT refined analysis DATE: 12/04/05 00:40:32 GMT FROM: Scott Barthelmy at NASA/GSFC T. N. Ukwatta (MSU), 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), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (OSU), G. Stratta (ASDC), J. Tueller (GSFC) (i.e. the Swift-BAT team): Using the data set from T-239 to T+963 sec from recent telemetry downlinks, we report further analysis of BAT GRB 120404A (trigger #519380) (Strata, et al., GCN Circ. 13208). The BAT ground-calculated position is RA, Dec = 235.002, 12.883 deg, which is RA(J2000) = 15h 40m 00.4s Dec(J2000) = +12d 52' 57.3" with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 49%. The mask-weighted light curve shows several overlapping peaks starting at ~T-20 sec, peaking at ~T+4 sec, and ending at ~T+80 sec. T90 (15-350 keV) is 38.7 +- 4.1 sec (estimated error including systematics). The time-averaged spectrum from T-7.31 to T+38.45 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.85 +- 0.13. The fluence in the 15-150 keV band is 1.6 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+3.29 sec in the 15-150 keV band is 1.2 +- 0.2 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/519380/BA/