TITLE:   GCN CIRCULAR
NUMBER:  33013
SUBJECT: GRB 221201A: Swift-BAT refined analysis
DATE:    22/12/03 15:01:15 GMT
FROM:    Tyler Parsotan at UMBC/GSFC/CRESST II  <parsotat@umbc.edu>

M. Stamatikos (OSU), S. D. Barthelmy (GSFC),

H. A. Krimm (NSF),, S. Laha (GSFC/UMBC),

A. Y. Lien (U Tampa),, C. B. Markwardt (GSFC),

D. M. Palmer (LANL),, T. Parsotan (GSFC/UMBC),

T. Sakamoto (AGU), (i.e. the Swift-BAT team):



Using the data set from T-239 to T+941 sec from the recent telemetry
downlink,

we report further analysis of BAT GRB 221201A (trigger #1142847)

(Troja et al., GCN Circ. 32998).  The BAT ground-calculated position is

RA, Dec = 266.903, -68.230 deg which is

   RA(J2000)  =  17h 47m 36.6s

   Dec(J2000) = -68d 13' 48.2"

with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).

The partial coding was 51%.



The mask-weighted light curve shows a single peaked pulse.

T90 (15-350 keV) is 33.71 +- 2.03 sec (estimated error including
systematics).



The time-averaged spectrum from T-20.88 to T+22.92 sec is best fit by a
simple

power-law model.  The power law index of the time-averaged spectrum is

1.63 +- 0.05.  The fluence in the 15-150 keV band is 8.6 +- 0.2 x 10^-06
erg/cm2.

The 1-sec peak photon flux measured from T-13.51 sec in the 15-150 keV band

is 11.2 +- 0.6 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/1142847/BA/