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    1.000 sec. to   11.088 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.4052     ( -0.176344   0.17501 )
Norm@50keV  : 4.02355E-03    ( -0.000417721   0.000415744 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          52.39 using 59 PHA bins.
# Reduced chi-squared =         0.9191 for     57 degrees of freedom 
# Null hypothesis probability =   6.485389e-01
 
Photon flux (15-150 keV)    in 10.09 sec: 0.490583 ( -0.050104  0.050152 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.91915e-07 ( -4.54484e-08  4.60117e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    1.000 sec. to   11.088 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.617615     ( -0.757798   0.931877 )
Epeak [keV] : 88.2368      ( -24.2328 549.017 )
Norm@50keV  : 9.96570E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          49.24 using 59 PHA bins.
# Reduced chi-squared =         0.8793 for     56 degrees of freedom 
# Null hypothesis probability =   7.266063e-01
 
Photon flux (15-150 keV)    in 10.09 sec: 0.473018 ( -0.05344  0.053104 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.68495e-07 ( -5.00083e-08  5.11492e-08 ) 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