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 -179.000 sec. to  963.064 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.83102     ( -0.318958   0.298458 )
Norm@50keV  : 1.99768E-04    ( -4.27465e-05   4.14519e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          63.18 using 59 PHA bins.
# Reduced chi-squared =          1.108 for     57 degrees of freedom 
# Null hypothesis probability =   2.672909e-01
 
Photon flux (15-150 keV)    in 1142 sec: 2.78672E-02 ( -0.0046232  0.0046239 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.09868e-06 ( -4.39219e-07  4.60122e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from -179.000 sec. to  963.064 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.44935     ( -0.755796   1.35019 )
Epeak [keV] : 57.0008      ( -49.8236 -57.0052 )
Norm@50keV  : 3.39882E-04    ( -0.000339803   0.00212706 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          62.76 using 59 PHA bins.
# Reduced chi-squared =          1.121 for     56 degrees of freedom 
# Null hypothesis probability =   2.492574e-01
 
Photon flux (15-150 keV)    in 1142 sec: 2.74676E-02 ( -0.0047115  0.004729 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.98393e-06 ( -5.14711e-07  4.98782e-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