TITLE: GCN CIRCULAR NUMBER: 29721 SUBJECT: GRB 210323A: Swift-BAT refined analysis DATE: 21/03/24 22:17:51 GMT FROM: Sibasish Laha at GSFC S. D. Barthelmy (GSFC), J. R. Cummings (CPI), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), 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-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 210323A (trigger #1038247) (Gropp et al., GCN Circ. 29699). The BAT ground-calculated position is RA, Dec = 317.945, 25.352 deg which is RA(J2000) = 21h 11m 46.7s Dec(J2000) = +25d 21' 08.7" with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 76%. The BAT lightcurve showed complex structure with a duration less than 2 sec. T90 (15-350 keV) is 1.12 +- 0.32 sec (estimated error including systematics). The time-averaged spectrum from T-0.09 to T+1.26 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.46 +- 0.17. The fluence in the 15-150 keV band is 2.4 +- 0.3 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T-0.10 sec in the 15-150 keV band is 2.9 +- 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/1038247/BA/