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   18.008 sec. to  369.732 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.53439     ( -0.0896471   0.0889584 )
Norm@50keV  : 2.96785E-03    ( -0.000142259   0.000141633 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   60.69     using 59 bins.
 Reduced chi-squared = 1.06474
# Null hypothesis probability of 3.44e-01 with 57 degrees of freedom
 
Photon flux (15-150 keV)    in 351.7 sec: 0.374047 ( -0.018174  0.018228 ) ph/cm2/s
Energy fluence (15-150 keV)             : 9.85013e-06 ( -5.15174e-07  5.18044e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   18.008 sec. to  369.732 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.43635     ( -0.177836   0.349967 )
Epeak [keV] : 300.137      ( -299.576 -299.576 )
Norm@50keV  : 3.30943E-03    ( -0.000469625   0.00151883 )
------------------------------------------------------------
#Fit statistic  : Chi-Squared                   60.43     using 59 bins.
 Reduced chi-squared = 1.07911
# Null hypothesis probability of 3.19e-01 with 56 degrees of freedom
 
Photon flux (15-150 keV)    in 351.7 sec: 0.371628 ( -0.019827  0.019715 ) ph/cm2/s
Energy fluence (15-150 keV)             : 9.77469e-06 ( -5.74386e-07  5.55595e-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