TITLE: GCN CIRCULAR NUMBER: 21313 SUBJECT: GRB 170710A: Swift-BAT refined analysis DATE: 17/07/10 17:03:52 GMT FROM: Amy Lien at GSFC A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), P. A. Evans (U Leicester), H. A. Krimm (NSF/USRA), 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+607 sec from the recent telemetry downlink, we report further analysis of BAT GRB 170710A (trigger #761119) (Evans et al., GCN Circ. 21308). The BAT ground-calculated position is RA, Dec = 231.851, -38.523 deg which is RA(J2000) = 15h 27m 24.2s Dec(J2000) = -38d 31' 22.2" with an uncertainty of 3.5 arcmin, (radius, sys+stat, 90% containment). The partial coding was 22%. The mask-weighted light curve shows a single-peaked structure that starts and peaks at ~T0, and ends at ~T+37 s. T90 (15-350 keV) is 32.6 +- 10.5 sec (estimated error including systematics). The time-averaged spectrum from T+0.16 to T+36.91 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.91 +- 0.37. The fluence in the 15-150 keV band is 7.4 +- 1.7 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.48 sec in the 15-150 keV band is 1.0 +- 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/761119/BA/