GRB 210226A: Swift-BAT refined analysis

Using the data set from T-240 to T+962 sec from the recent telemetry downlink, we report further analysis of BAT GRB 210226A (trigger #1034721) (Beardmore, et al., GCN Circ. 29568). The BAT ground-calculated position is RA, Dec = 124.153, 57.585 deg which is RA(J2000) = 08h 16m 36.7s Dec(J2000) = +57d 35' 06.9" with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment). The partial coding was 47%. The BAT light curve showed a complex structure with a duration of about ~30 sec. T90 (15-350 keV) is 20.80 +- 1.68 sec (estimated error including systematics). The time-averaged spectrum from T-1.92 to T+20.95 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.44 +- 0.15. The fluence in the 15-150 keV band is 1.2 +- 0.1 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+0.02 sec in the 15-150 keV band is 2.8 +- 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/1034721/BA/