TITLE: GCN CIRCULAR NUMBER: 21195 SUBJECT: GRB 170604A: Swift-BAT refined analysis DATE: 17/06/05 02:19:40 GMT FROM: Amy Lien at GSFC M. Stamatikos (OSU), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL), T. Sakamoto (AGU), 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 170604A (trigger #755867) (Page et al., GCN Circ. 21191). The BAT ground-calculated position is RA, Dec = 342.645, -15.406 deg which is RA(J2000) = 22h 50m 34.9s Dec(J2000) = -15d 24' 20.1" with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 8%. The mask-weighted light curve shows several overlapping pulses that start at ~ T-12 s and end at ~T+20 s. The main peak occurs at ~T+3 s. T90 (15-350 keV) is 26.70 +- 6.21 sec (estimated error including systematics). The time-averaged spectrum from T-11.66 to T+22.58 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.31 +- 0.12. The fluence in the 15-150 keV band is 5.1 +- 0.4 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+2.66 sec in the 15-150 keV band is 4.2 +- 0.9 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/755867/BA/