TITLE: GCN CIRCULAR NUMBER: 19263 SUBJECT: GRB 160408A: Swift-BAT refined analysis DATE: 16/04/08 13:13:33 GMT FROM: Scott Barthelmy at NASA/GSFC D. M. Palmer (LANL), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), P.A. Evans (U Leicester), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-120 to T+302 sec from the recent telemetry downlinks, we report further analysis of BAT GRB 160408A (trigger #682059) (Evans, et al., GCN Circ. 19260). The BAT ground-calculated position is RA, Dec = 122.561, 71.128 deg, which is RA(J2000) = 08h 10m 14.6s Dec(J2000) = +71d 07' 40.0" with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment). The partial coding was 33%. The mask-weighted light curve starts at ~T0, peaks at ~T+0.1 sec, and ends at ~T+0.4 sec. T90 (15-350 keV) is 0.32 +- 0.04 sec (estimated error including systematics). The time-averaged spectrum from T+0.02 to T+0.37 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 0.85 +- 0.25. The fluence in the 15-150 keV band is 1.6 +- 0.2 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.30 sec in the 15-150 keV band is 2.1 +- 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/682059/BA/ We note that this burst was detected by Fermi-GBM, CALET-GBM, Swift-BAT, and INTEGRAL-SPIACS.