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 -2.728 sec. to 23.288 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.94384 ( -0.336631 0.309294 )
Norm@50keV : 1.21028E-03 ( -0.000280404 0.000272533 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 80.54 using 59 bins.
Reduced chi-squared = 1.41298
# Null hypothesis probability of 2.18e-02 with 57 degrees of freedom
Photon flux (15-150 keV) in 26.02 sec: 0.177023 ( -0.030979 0.030984 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.89806e-07 ( -6.29354e-08 6.58891e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.728 sec. to 23.288 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.637247 ( -1.58898 2.97674 )
Epeak [keV] : 38.2440 ( -37.9963 80.5102 )
Norm@50keV : 7.96806E-03 ( -0.00847553 0.791566 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 78.74 using 59 bins.
Reduced chi-squared = 1.40607
# Null hypothesis probability of 2.42e-02 with 56 degrees of freedom
Photon flux (15-150 keV) in 26.02 sec: 0.169720 ( -0.031603 0.032198 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.44145e-07 ( -6.46311e-08 8.5873e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.132 sec. to 0.868 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.41181 ( -0.584754 0.60216 )
Norm@50keV : 4.25328E-03 ( -0.00135168 0.00131658 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 69.66 using 59 bins.
Reduced chi-squared = 1.22211
# Null hypothesis probability of 1.21e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.519384 ( -0.15975 0.160246 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.10053e-08 ( -1.42044e-08 1.48044e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.132 sec. to 0.868 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.4232 ( -0.577941 1.0543 )
Epeak [keV] : 9999.30 ( -9999.36 -9999.36 )
Norm@50keV : 4.23822E-03 ( -0.00135583 0.0471917 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 69.66 using 59 bins.
Reduced chi-squared = 1.24393
# Null hypothesis probability of 1.04e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.520802 ( -0.161533 0.159299 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.19411e-08 ( -1.62342e-08 1.35994e-08 ) ergs/cm2
Time-resolved spectra
