TITLE: GCN CIRCULAR NUMBER: 29409 SUBJECT: GRB 210205A: Swift-BAT refined analysis DATE: 21/02/06 03:36:38 GMT FROM: Amy Lien at GSFC S. D. Barthelmy (GSFC), J. R. Cummings (CPI), S. Dichiara (NASA/GSFC/UMCP), 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 210205A (trigger #1030629) (Dichiara et al., GCN Circ. 29397). The BAT ground-calculated position is RA, Dec = 347.264, 56.311 deg which is RA(J2000) = 23h 09m 03.3s Dec(J2000) = +56d 18' 41.2" with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 18%. The mask-weighted light curve shows a multi-peaked structure that starts at ~ T-7 s and ends at ~T+20 s. The main peak in the structure occurs at ~T+6 s. T90 (15-350 keV) is 22.70 +- 4.18 sec (estimated error including systematics). The time-averaged spectrum from T-7.35 to T+20.07 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.27 +- 0.31. The fluence in the 15-150 keV band is 8.7 +- 1.6 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+5.98 sec in the 15-150 keV band is 1.6 +- 0.5 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/1030629/BA/