TITLE:   GCN CIRCULAR
NUMBER:  7359
SUBJECT: GRB 080303, Swift-BAT refined analysis
DATE:    08/03/03 23:05:07 GMT
FROM:    Takanori Sakamoto at NASA/GSFC  <Taka.Sakamoto@nasa.gov>

T. Sakamoto (GSFC/UMBC), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC),
E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), 
C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD), D. Palmer (LANL),
A. Parsons (GSFC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 080303 (trigger #304549)
(Sakamoto, et al., GCN Circ. 7351).  The BAT ground-calculated position is
RA, Dec = 112.019, -70.231 deg which is 
   RA(J2000)  = 7h 28m 4.6s 
   Dec(J2000) = -70d 13' 53" 
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 80%.
 
The mask-weighted light curve shows a FRED-like peak T-1 sec, peaking at 
T+0.5 sec, and ending at T+20 sec.  There is also an extended emission until 
T+~90 sec.  T90 (15-350 keV) is 67 +- 20 sec (estimated error including systematics).
 
The time-averaged spectrum from T-0.2 to T+73.2 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.54 +- 0.25.  The fluence in the 15-150 keV band is 6.6 +- 1.0 x 10^-7 erg/cm2.  
The 1-sec peak photon flux measured from T+0.06 sec in the 15-150 keV band
is 1.4 +- 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/304549/BA/