Notes:

• 1) The fitting includes the systematic errors.
• 2) When the burst includes telescope slew time periods, the fitting uses an average response file made from multiple 5-s response files through out the slew time plus single time preiod for the non-slew times, and weighted by the total counts in the corresponding time period using addrmf. An average response file is needed becuase a spectral fit using the pre-slew DRM will introduce some errors in both a spectral shape and a normalization if the PHA file contains a lot of the slew/post-slew time interval.
• 3) For fits to more complicated models (e.g. a power-law over a cutoff power-law), the BAT team has decided to require a chi-square improvement of more than 6 for each extra dof.

Time averaged spectrum fit using the average DRM

Power-law model

Time interval is from    0.000 sec. to    0.064 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.65734     ( -0.517759   0.512945 )
Norm@50keV  : 9.52976E-03    ( -0.00400619   0.00387336 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.86 using 59 PHA bins.
# Reduced chi-squared =          1.050 for     57 degrees of freedom 
# Null hypothesis probability =   3.721954e-01
 
Photon flux (15-150 keV)    in 0.064 sec: 1.25636 ( -0.522921  0.52015 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.61242e-09 ( -2.3685e-09  2.41489e-09 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    0.000 sec. to    0.064 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 2.75404     ( -2.68302   7.1913 )
Epeak [keV] : 57.0409      ( -15.6592 16.7986 )
Norm@50keV  : 1.26091    ( -1.5114   12053.1 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          49.95 using 59 PHA bins.
# Reduced chi-squared =         0.8919 for     56 degrees of freedom 
# Null hypothesis probability =   7.020566e-01
 
Photon flux (15-150 keV)    in 0.064 sec: 1.23753 ( -0.443258  0.49752 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.92257e-09 ( -2.31977e-09  2.50961e-09 ) ergs/cm2
 

1-s peak spectrum fit

1-s peak spectrum unavailable, likely because there are no event data in the 1-s peak range.

Time-resolved spectra