TITLE: GCN CIRCULAR NUMBER: 19529 SUBJECT: GRB 160611A: Swift-BAT refined analysis DATE: 16/06/12 18:47:00 GMT FROM: Hans Krimm at NASA-GSFC T. Sakamoto (AGU), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), D. Malesani (DARK/NBI), 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+962 sec from the recent telemetry downlink, we report further analysis of BAT GRB 160611A (trigger #690598) (Malesani, et al., GCN Circ. 19522). The BAT ground-calculated position is RA, Dec = 164.417, -70.396 deg which is RA(J2000) = 10h 57m 40.0s Dec(J2000) = -70d 23' 45.8" with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 45%. The mask-weighted light curve shows a single episode with several overlapping pulses. The emission starts at T-15 sec, peaks at T+3 sec and ends at T+20 sec. T90 (15-350 keV) is 34.1 +- 5.6 sec (estimated error including systematics). A pre-planned spacecraft slew moved the source out of the field of view at about T+165 sec. The time-averaged spectrum from T-31.38 to T+10.37 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.67 +- 0.12. The fluence in the 15-150 keV band is 1.7 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+2.84 sec in the 15-150 keV band is 2.0 +- 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/690598/BA/