TITLE: GCN CIRCULAR NUMBER: 28545 SUBJECT: GRB 201001A: Swift-BAT refined analysis DATE: 20/10/01 20:46:52 GMT FROM: Hans Krimm at NSF/NASA-GSFC T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), K. K. Simpson (PSU), M. Stamatikos (OSU), (i.e. the Swift-BAT team): Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 201001A (trigger #998344) (Simpson, et al., GCN Circ. 28539). The BAT ground-calculated position is RA, Dec = 110.050, -2.213 deg which is RA(J2000) = 07h 20m 12.0s Dec(J2000) = -02d 12' 48.3" with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 38%. The mask-weighted light curve shows a broad single peak of duration roughly 20 seconds, from ~T-5 to ~T+15 sec. T90 (15-350 keV) is 15.2 +- 2.7 sec (estimated error including systematics). The time-averaged spectrum from T-4.02 to T+12.98 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 0.96 +- 0.23. The fluence in the 15-150 keV band is 7.6 +- 1.1 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+10.79 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/998344/BA/