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 -0.256 sec. to 8.704 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.38047 ( -0.041581 0.0415988 )
Norm@50keV : 4.61936E-02 ( -0.00100214 0.00100182 )
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#Fit statistic : Chi-Squared = 55.08 using 59 PHA bins.
# Reduced chi-squared = 0.9664 for 57 degrees of freedom
# Null hypothesis probability = 5.473267e-01
Photon flux (15-150 keV) in 8.96 sec: 5.60119 ( -0.13582 0.1364 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.01613e-06 ( -9.08759e-08 9.09942e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.256 sec. to 8.704 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.37563 ( -0.084234 0.170213 )
Epeak [keV] : 9996.08 ( -845.031 -845.031 )
Norm@50keV : 4.64570E-02 ( -0.00424351 0.0083123 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.07 using 59 PHA bins.
# Reduced chi-squared = 0.9835 for 56 degrees of freedom
# Null hypothesis probability = 5.099329e-01
Photon flux (15-150 keV) in 8.96 sec: 3.32902 ( -0.19893 0.15952 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.00606e-06 ( -9.73997e-08 9.36006e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.108 sec. to 2.108 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.48732 ( -0.0709083 0.0704796 )
Norm@50keV : 8.33346E-02 ( -0.0032392 0.00323221 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.98 using 59 PHA bins.
# Reduced chi-squared = 0.8242 for 57 degrees of freedom
# Null hypothesis probability = 8.254309e-01
Photon flux (15-150 keV) in 1 sec: 10.3686 ( -0.41328 0.4139 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.92319e-07 ( -3.3689e-08 3.38141e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.108 sec. to 2.108 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.37114 ( -0.152544 0.274832 )
Epeak [keV] : 286.685 ( -286.686 -286.686 )
Norm@50keV : 9.47419E-02 ( -0.0140299 0.0325623 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.41 using 59 PHA bins.
# Reduced chi-squared = 0.8288 for 56 degrees of freedom
# Null hypothesis probability = 8.158578e-01
Photon flux (15-150 keV) in 1 sec: 10.2985 ( -0.44056 0.4412 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.86122e-07 ( -3.66421e-08 3.63858e-08 ) ergs/cm2
Time-resolved spectra
