TITLE: GCN CIRCULAR NUMBER: 15934 SUBJECT: GRB 140305A: Swift-BAT refined analysis DATE: 14/03/05 23:43:35 GMT FROM: Takanori Sakamoto at AGU J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/UMBC), C. B. Markwardt (GSFC), A. Maselli (INAF-IASFPA), D. M. Palmer (LANL), T. Sakamoto (AGU), 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+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 140305A (trigger #590446) (Maselli, et al., GCN Circ. 15929). The BAT ground-calculated position is RA, Dec = 344.497, 15.448 deg which is RA(J2000) = 22h 57m 59.4s Dec(J2000) = +15d 26' 53.3" with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 48%. The mask-weighted light curve shows a FRED-like peak starting at T-1 sec, peaking at T+0 sec, and ending at T+20 sec. T90 (15-350 keV) is 13.7 +- 1.8 sec (estimated error including systematics). The time-averaged spectrum from T-1.1 to T+16.3 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.32 +- 0.92, and Epeak of 70 +- 32 keV (chi squared 45.13 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 4.7 +- 0.7 x 10^-7 erg/cm2 and the 1-sec peak flux measured from T+0.18 sec in the 15-150 keV band is 1.0 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.49 +- 0.17 (chi squared 51.59 for 57 d.o.f.). 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/590446/BA/ [GCN OPS NOTE(05mar14): Per author's request, the peak time was changed from "T" to "T+0".]