TITLE: GCN CIRCULAR NUMBER: 21331 SUBJECT: GRB 170711A: Swift-BAT refined analysis DATE: 17/07/12 19:23:15 GMT FROM: Hans Krimm at NSF/NASA-GSFC C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), V. D'Elia (ASDC), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), 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 170711A (trigger #761622) (D'Elia, et al., GCN Circ. 21321). The BAT ground-calculated position is RA, Dec = 45.782, 47.845 deg which is RA(J2000) = 03h 03m 07.7s Dec(J2000) = +47d 50' 41.2" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%. The mask-weighted light curve shows a single FRED-shaped peak, starting at T-2 sec, peaking at T+0 sec and decaying to background by T+6 sec. This is preceded by some weak, soft emission beginning at about T-25 sec. T90 (15-350 keV) is 31.3 +- 7.6 sec (estimated error including systematics). The time-averaged spectrum from T-31.66 to T+15.37 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.75 +- 0.10. The fluence in the 15-150 keV band is 1.4 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+0.02 sec in the 15-150 keV band is 4.8 +- 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/761622/BA/