TITLE: GCN CIRCULAR NUMBER: 18699 SUBJECT: GRB 151215A: Swift-BAT refined analysis DATE: 15/12/15 22:29:18 GMT FROM: Tilan Ukwatta at LANL J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), N. Gehrels (GSFC), S. L. Gibson (U Leicester) H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-240 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 151215A (trigger #667392) (Gibson, et al., GCN Circ. 18691). The BAT ground-calculated position is RA, Dec = 93.622, 35.529 deg which is RA(J2000) = 06h 14m 29.3s Dec(J2000) = +35d 31' 45.0" with an uncertainty of 2.8 arcmin, (radius, sys+stat, 90% containment). The partial coding was 51%. The mask-weighted light curve shows a multi-peak episode starting ~T-15 sec, highest peak at ~T+0 sec, and the episode ends around ~T+5 sec. T90 (15-350 keV) is 17.8 +- 1.0 sec (estimated error including systematics). The time-averaged spectrum from T-15.46 to T+3.13 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.99 +- 0.33. The fluence in the 15-150 keV band is 3.1 +- 0.7 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T-0.16 sec in the 15-150 keV band is 1.6 +- 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/667392/BA/