TITLE: GCN CIRCULAR NUMBER: 16799 SUBJECT: GRB 140907A: Swift-BAT refined analysis DATE: 14/09/08 16:12:53 GMT FROM: Hans Krimm at NASA-GSFC T. Sakamoto (AGU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 140907A (trigger #611933) (Krimm, et al., GCN Circ. 16788). The BAT ground-calculated position is RA, Dec = 48.133, 46.596 deg which is RA(J2000) = 03h 12m 31.9s Dec(J2000) = +46d 35' 43.8" with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 65%. The mask-weighted light curve shows a single peak with superimposed spikes, running from approximately T-10 to T+40 sec. T90 (15-350 keV) is 79.2 +- 31.4 sec (estimated error including systematics). The time-averaged spectrum from T-91.2 to T+39.9 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.72 +- 0.07. The fluence in the 15-150 keV band is 4.3 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+17.47 sec in the 15-150 keV band is 2.5 +- 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/611933/BA/