TITLE: GCN CIRCULAR NUMBER: 32453 SUBJECT: GRB 220806A: Swift-BAT refined analysis DATE: 22/08/09 21:27:59 GMT FROM: Sibasish Laha at GSFC sibasish.laha@nasa.gov

D. M. Palmer (LANL),S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU), 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 220806A (trigger #1119268) (Page et al., GCN Circ. 32445). The BAT ground-calculated position is RA, Dec = 260.858, -26.021 deg which is RA(J2000) = 17h 23m 26.0s Dec(J2000) = -26d 01' 15.2" with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%.

The BAT light curve showed a single peaked structure with a duration of about 6 sec. T90 (15-350 keV) is 4.78 +- 2.00 sec (estimated error including systematics).

The time-averaged spectrum from T-0.30 to T+6.66 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.81 +- 0.33. The fluence in the 15-150 keV band is 1.5 +- 0.3 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T+0.76 sec in the 15-150 keV band is 1.1 +- 0.2 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/1119268/BA/