TITLE: GCN CIRCULAR NUMBER: 16090 SUBJECT: GRB 140408A: Swift-BAT refined analysis DATE: 14/04/09 14:31:03 GMT FROM: Amy Lien at GSFC T. N. Ukwatta (MSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), V. D'Elia (ASDC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), (i.e. the Swift-BAT team): Using the data set from T-180 to T+902 sec from the recent telemetry downlink, we report further analysis of BAT GRB 140408A (trigger #595141) (D'Elia, et al., GCN Circ. 16082). The BAT ground-calculated position is RA, Dec = 290.723, -12.585 deg which is RA(J2000) = 19h 22m 53.5s Dec(J2000) = -12d 35' 07.7" with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 40%. The mask-weighted light curve shows a single-pulse structure starts at ~T-1 sec, peaks at ~ T+1 sec, and ends at ~T+4 sec. T90 (15-350 keV) is 4.00 +- 1.41 sec (estimated error including systematics). The time-averaged spectrum from T-0.66 to T+3.34 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.49 +- 0.25. The fluence in the 15-150 keV band is 3.1 +- 0.5 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.34 sec in the 15-150 keV band is 1.2 +- 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/595141/BA/