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 -0.156 sec. to 83.348 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.35148 ( -0.485282 0.481681 )
Norm@50keV : 3.24044E-04 ( -0.000105834 0.000105353 )
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#Fit statistic : Chi-Squared = 79.25 using 59 PHA bins.
# Reduced chi-squared = 1.390 for 57 degrees of freedom
# Null hypothesis probability = 2.731207e-02
Photon flux (15-150 keV) in 83.5 sec: 3.90401E-02 ( -0.0125265 0.0126071 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.64476e-07 ( -9.27184e-08 9.66396e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.156 sec. to 83.348 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.25996 ( -3.89855 -3.51879 )
Epeak [keV] : 52.7195 ( -10.2908 31.7793 )
Norm@50keV : 8.02692E-02 ( -0.0772621 219.17 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 73.27 using 59 PHA bins.
# Reduced chi-squared = 1.308 for 56 degrees of freedom
# Null hypothesis probability = 6.053977e-02
Photon flux (15-150 keV) in 83.5 sec: 3.45320E-02 ( -0.0125957 0.0128289 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.04558e-07 ( -7.23111e-08 9.36478e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.452 sec. to 1.452 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.926946 ( -0.367905 0.397051 )
Norm@50keV : 4.79374E-03 ( -0.00104575 0.001037 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.79 using 59 PHA bins.
# Reduced chi-squared = 1.154 for 57 degrees of freedom
# Null hypothesis probability = 1.987962e-01
Photon flux (15-150 keV) in 1 sec: 0.550424 ( -0.11999 0.120498 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.32513e-08 ( -1.24062e-08 1.25948e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.452 sec. to 1.452 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.290651 ( -0.966731 2.26028 )
Epeak [keV] : 148.928 ( -148.954 -148.954 )
Norm@50keV : 9.38672E-03 ( -0.00547917 0.0769161 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.32 using 59 PHA bins.
# Reduced chi-squared = 1.166 for 56 degrees of freedom
# Null hypothesis probability = 1.845628e-01
Photon flux (15-150 keV) in 1 sec: 0.535788 ( -0.127259 0.125835 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.09988e-08 ( -1.40806e-08 1.37706e-08 ) ergs/cm2
Time-resolved spectra
