TITLE: GCN CIRCULAR NUMBER: 17701 SUBJECT: GRB 150413A: Swift-BAT refined analysis DATE: 15/04/14 14:03:03 GMT FROM: Amy Lien at GSFC M. Stamatikos (OSU), 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), T. Sakamoto (AGU), 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 150413A (trigger #637899) (Markwardt, et al., GCN Circ. 17688). The BAT ground-calculated position is RA, Dec = 190.396, 71.839 deg which is RA(J2000) = 12h 41m 35.1s Dec(J2000) = +71d 50' 21.9" with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 35%. The mask-weighted light curve shows a multi-peaked structure that starts at ~ T-100 s and ends at ~ T+200 s. The most prominent pulse starts at ~ T+90 s, peaks at ~ T+110 s, and ends at ~ T+120 s. T90 (15-350 keV) is 263.6 +- 36.7 sec (estimated error including systematics). The time-averaged spectrum from T-93.0 to T+209.8 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.75 +- 0.14. The fluence in the 15-150 keV band is 4.3 +- 0.4 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+110.78 sec in the 15-150 keV band is 1.6 +- 0.3 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/637899/BA/