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 -42.252 sec. to 21.464 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.78299 ( -0.221158 0.212893 )
Norm@50keV : 1.66490E-03 ( -0.000240484 0.000236858 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.13 using 59 PHA bins.
# Reduced chi-squared = 1.266 for 57 degrees of freedom
# Null hypothesis probability = 8.540504e-02
Photon flux (15-150 keV) in 63.72 sec: 0.227934 ( -0.029731 0.029764 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.77478e-07 ( -1.42883e-07 1.45099e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -42.252 sec. to 21.464 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.276167 ( -1.08018 1.49367 )
Epeak [keV] : 50.8025 ( -9.25881 23.0345 )
Norm@50keV : 1.12191E-02 ( -0.0112194 0.0636629 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.88 using 59 PHA bins.
# Reduced chi-squared = 1.177 for 56 degrees of freedom
# Null hypothesis probability = 1.720181e-01
Photon flux (15-150 keV) in 63.72 sec: 0.216530 ( -0.030985 0.030878 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.72926e-07 ( -1.47729e-07 1.58661e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.032 sec. to 1.032 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.45021 ( -0.312167 0.309906 )
Norm@50keV : 1.11285E-02 ( -0.00203781 0.002026 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.86 using 59 PHA bins.
# Reduced chi-squared = 0.9098 for 57 degrees of freedom
# Null hypothesis probability = 6.678792e-01
Photon flux (15-150 keV) in 1 sec: 1.37153 ( -0.25283 0.25361 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.065e-07 ( -2.11586e-08 2.14411e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.032 sec. to 1.032 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.892991 ( -0.829528 1.56117 )
Epeak [keV] : 102.161 ( -45.1755 -102.161 )
Norm@50keV : 2.09935E-02 ( -0.0116217 0.0942754 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.25 using 59 PHA bins.
# Reduced chi-squared = 0.9151 for 56 degrees of freedom
# Null hypothesis probability = 6.550845e-01
Photon flux (15-150 keV) in 1 sec: 1.33992 ( -0.26463 0.26297 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.02809e-07 ( -2.27205e-08 2.28779e-08 ) ergs/cm2
Time-resolved spectra
