TITLE:   GCN CIRCULAR
NUMBER:  10801
SUBJECT: GRB 100526A: Swift-BAT refined analysis
DATE:    10/05/26 20:11:43 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

W. H. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD),
D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. N. Ukwatta (GWU), L. Vetere (PSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-239 to T+303 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 100526A (trigger #423181)
(Vetere, et al., GCN Circ. 10797).  The BAT ground-calculated position is
RA, Dec = 230.792, 25.623 deg which is 
   RA(J2000)  =  15h 23m 10.2s 
   Dec(J2000) = +25d 37' 24.4" 
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 26%.
 
The mask-weighted light curve shows a few overlapping peaks starting at
~T-70 sec, peaking around T-20 and at ~T+75 sec, and ending at ~T+115 sec.
T90 (15-350 keV) is 102 +- 8.5 sec (estimated error including systematics).
 
The time-averaged spectrum from T-33.2 to T+80.0 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.83 +- 0.17.  The fluence in the 15-150 keV band is 2.5 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+69.90 sec in the 15-150 keV band
is 0.7 +- 0.3 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/423181/BA/