TITLE:   GCN CIRCULAR
NUMBER:  8735
SUBJECT: GRB 081226A: Swift-BAT refined analysis
DATE:    08/12/26 16:12:39 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
O. Godet (U Leicester) C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 081226A (trigger #338177)
(Godet, et al., GCN Circ. 8729).  The BAT ground-calculated position is
RA, Dec = 120.478, -69.014 deg, which is 
   RA(J2000)  =  08h 01m 54.6s 
   Dec(J2000) = -69d 00' 48.6" 
with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 32%.
 
The mask-weighted light curve shows a single spike starting at T+0.0 and
ending at T+0.4 sec.  T90 (15-350 keV) is 0.4 +- 0.1 sec (estimated error
including systematics).
 
The time-averaged spectrum from T-0.1 to T+0.5 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.36 +- 0.29.  The fluence in the 15-150 keV band is 9.9 +- 1.8 x 10^-8 erg/cm2.
The 1-sec peak photon flux measured from T-0.30 sec in the 15-150 keV band
is 2.4 +- 0.4 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/338177/BA/