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 -0.796 sec. to 10.996 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.66255 ( -0.069849 0.0695597 )
Norm@50keV : 2.25587E-02 ( -0.000866192 0.00086533 )
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#Fit statistic : Chi-Squared = 51.83 using 59 PHA bins.
# Reduced chi-squared = 0.9094 for 57 degrees of freedom
# Null hypothesis probability = 6.686763e-01
Photon flux (15-150 keV) in 11.79 sec: 2.95803 ( -0.12268 0.1231 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.47089e-06 ( -9.8621e-08 9.89373e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.796 sec. to 10.996 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.36677 ( -0.272546 0.291101 )
Epeak [keV] : 111.682 ( -31.5797 484.718 )
Norm@50keV : 3.13382E-02 ( -0.00800443 0.0116357 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.39 using 59 PHA bins.
# Reduced chi-squared = 0.8640 for 56 degrees of freedom
# Null hypothesis probability = 7.552493e-01
Photon flux (15-150 keV) in 11.79 sec: 2.90060 ( -0.13272 0.13316 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.42138e-06 ( -1.09351e-07 1.08869e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 4.716 sec. to 5.716 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.43002 ( -0.0933957 0.0934425 )
Norm@50keV : 7.34309E-02 ( -0.00398025 0.00397768 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.38 using 59 PHA bins.
# Reduced chi-squared = 0.7962 for 57 degrees of freedom
# Null hypothesis probability = 8.662063e-01
Photon flux (15-150 keV) in 1 sec: 9.00555 ( -0.51185 0.51272 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.05407e-07 ( -4.11441e-08 4.12824e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 4.716 sec. to 5.716 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.27771 ( -0.201629 0.371361 )
Epeak [keV] : 250.199 ( -250.212 -250.212 )
Norm@50keV : 8.71339E-02 ( -0.0169751 0.0437542 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.83 using 59 PHA bins.
# Reduced chi-squared = 0.8005 for 56 degrees of freedom
# Null hypothesis probability = 8.579353e-01
Photon flux (15-150 keV) in 1 sec: 5.01071 ( -0.63919 0.62336 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.99471e-07 ( -4.37033e-08 4.34284e-08 ) ergs/cm2
Time-resolved spectra
