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    4.000 sec. to   14.080 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.54729     ( -0.292153   0.290772 )
Norm@50keV  : 1.00971E-02    ( -0.00179828   0.00179543 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          53.17 using 59 PHA bins.
# Reduced chi-squared =         0.9328 for     57 degrees of freedom 
# Null hypothesis probability =   6.194690e-01
 
Photon flux (15-150 keV)    in 10.08 sec: 1.27728 ( -0.24017  0.24188 ) ph/cm2/s
Energy fluence (15-150 keV)             : 9.58651e-07 ( -1.78174e-07  1.7903e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    4.000 sec. to   14.080 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.782933     ( -0.96177   1.40197 )
Epeak [keV] : 84.3322      ( -30.3828 -84.3323 )
Norm@50keV  : 2.36810E-02    ( -0.0148272   0.0835676 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          51.83 using 59 PHA bins.
# Reduced chi-squared =         0.9256 for     56 degrees of freedom 
# Null hypothesis probability =   6.331976e-01
 
Photon flux (15-150 keV)    in 10.08 sec: 1.24085 ( -0.245428  0.24756 ) ph/cm2/s
Energy fluence (15-150 keV)             : 9.30016e-07 ( -1.85232e-07  1.85204e-07 ) 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