TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  5538
SUBJECT: GRB 060906, Swift-BAT refined spectral analysis
DATE:    06/09/06 21:14:38 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@lheamail.gsfc.nasa.gov>

G. Sato (GSFC/ISAS), T. Sakamoto (GSFC/ORAU), C. Markwardt (GSFC/UMD),
D. Palmer (LANL), S. D. Barthelmy (GSFC), L. Barbier (GSFC),
J. Cummings (GSFC/UMD), E. Fenimore (LANL), N. Gehrels (GSFC),
D. Hullinger (BYU-Idaho), H. Krimm (GSFC/USRA), A. Parsons (GSFC),
J.L. Racusin (PSU), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC)
on behalf of the Swift-BAT team:
 
We report the spectral analysis of Swift-BAT GRB 060906 (trigger #228316)
(Racusin, et al., GCN Circ. 5528; & Sakamoto, et al., GCN Circ. 5534).
Using the response matrix appropriate for the burst position in the 
BAT field-of-view during the slew: 
The time-averaged spectrum from T-41.8 to T+6.0 is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum
is 2.02 +- 0.11.  The fluence in the 15-150 keV band is
2.21 +- 0.14 x 10^-6 erg/cm2.  The 1-sec peak photon flux measured
from T-24.86 sec in the 15-150 keV band is 2.0 +- 0.3 ph/cm2/sec.
All the quoted errors are at the 90% confidence level.