TITLE:   GCN CIRCULAR
NUMBER:  10932
SUBJECT: GRB 100704A: Swift-BAT refined analysis
DATE:    10/07/04 11:58:03 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), D. Grupe (PSU),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
A. M. Parsons (GSFC), 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 100704A (trigger #426722)
(Grupe, et al., GCN Circ. 10929).  The BAT ground-calculated position is
RA, Dec = 133.639, -24.202 deg, which is 
   RA(J2000)  =  08h 54m 33.3s 
   Dec(J2000) = -24d 12' 08.0" 
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 85%.
 
The mask-weighted light curve shows an initial very weak peak starting at ~T-70 sec
and peaking at ~T-60 sec.  Then comes the main peak starting at ~T-5 sec,
peaking at ~T+1.5 sec, and ending at ~T+50 sec.  That is followed by a small peak
at ~T+100 sec, and then a larger peak from ~T+140 to ~T+210 sec.
T90 (15-350 keV) is 197.5 +- 23.3 sec (estimated error including systematics).
 
The time-averaged spectrum from T-62.3 to T+202.3 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.73 +- 0.06.  The fluence in the 15-150 keV band is 6.0 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+0.76 sec in the 15-150 keV band
is 4.3 +- 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/426722/BA/