TITLE:   GCN CIRCULAR
NUMBER:  11283
SUBJECT: GRB 100915A: Correction to Swift-BAT refined analysis
DATE:    10/09/15 14:56:36 GMT
FROM:    Takanori Sakamoto at NASA/GSFC  <takanori@milkyway.gsfc.nasa.gov>

T. Sakamoto (GSFC/UMBC), S. D. Barthelmy (GSFC) 
(i.e. the Swift-BAT team):

We would like to make corrections to the BAT refined analysis of GRB 100915A 
(GCN Circ. 11281).  The BAT time-averaged spectrum is best fit by a simple 
power-law (PL) model rather than a power-law with an exponential cutoff (CPL) 
model.  We believe a low signal to noise in the observed spectrum of this burst 
causes a significant improvement in chi2 by a CPL model over a PL model.  We 
would like to correct the 3rd paragraph of GCN Circ. 11281 to:

"The time-averaged spectrum from T-36.3 to T+72.2 sec is best fit by a simple 
power-law model.  The power law index of the time-averaged spectrum is
1.50 +- 0.24.  The fluence in the 15-150 keV band is 1.5 +- 0.2 x 10^-06 erg/cm2.
The 1-sec peak photon flux measured from T+8.76 sec in the 15-150 keV band
is 0.5 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. "

We apologize for possible inconvenience.  We would like to thank Eleonora Troja 
for pointing this issue.