TITLE: GCN CIRCULAR NUMBER: 30495 SUBJECT: GRB 210723A: Swift-BAT refined analysis DATE: 21/07/24 20:28:49 GMT FROM: Amy Lien at GSFC H. A. Krimm (NSF), S. D. Barthelmy (GSFC), S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), T. Sbarrato (INAF-OAB), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-239 to T+861 sec from the recent telemetry downlink, we report further analysis of BAT GRB 210723A (trigger #1061284) (Sbarrato et al., GCN Circ. 30485). The BAT ground-calculated position is RA, Dec = 121.723, -32.893 deg which is RA(J2000) = 08h 06m 53.4s Dec(J2000) = -32d 53' 35.8" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 77%. The mask-weighted light curve shows a single-pulse structure that starts at ~T-5 s, peaks at ~T0, and ends at ~T+65 s. T90 (15-350 keV) is 48.54 +- 3.50 sec (estimated error including systematics). The time-averaged spectrum from T-4.59 to T+66.64 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.85 +- 0.29, and Epeak of 88.2 +- 15.3 keV (chi squared 54.48 for 52 d.o.f.). For this model the total fluence in the 15-150 keV band is 5.3 +- 0.2 x 10^-6 erg/cm2 and the 1-sec peak flux measured from T+2.68 sec in the 15-150 keV band is 3.1 +- 0.3 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.60 +- 0.06 (chi squared 75.55 for 53 d.o.f.). 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/1061284/BA/