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 -13.244 sec. to 25.796 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.21744 ( -0.275695 0.279872 )
Norm@50keV : 1.90562E-03 ( -0.000259102 0.000258463 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.89 using 59 PHA bins.
# Reduced chi-squared = 1.016 for 57 degrees of freedom
# Null hypothesis probability = 4.422032e-01
Photon flux (15-150 keV) in 39.04 sec: 0.224247 ( -0.031114 0.031267 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.51188e-07 ( -1.18733e-07 1.20819e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -13.244 sec. to 25.796 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.14785 ( -0.69212 1.24813 )
Epeak [keV] : 53.3538 ( )
Norm@50keV : 5.90396E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.70 using 59 PHA bins.
# Reduced chi-squared = 1.012 for 56 degrees of freedom
# Null hypothesis probability = 4.488946e-01
Photon flux (15-150 keV) in 39.04 sec: 0.224226 ( -0.031198 0.031203 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.50396e-07 ( -1.18377e-07 1.21129e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -4.316 sec. to -3.316 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: 2.10194 ( -2.33913 0.720059 )
Norm@50keV : 2.86290E-04 ( -0.000290132 0.0035707 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.38 using 59 PHA bins.
# Reduced chi-squared = 1.147 for 57 degrees of freedom
# Null hypothesis probability = 2.087096e-01
Photon flux (15-150 keV) in 1 sec: 0.408909 ( -0.408909 0.074177 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.70637e-08 ( -2.15038e-08 2.07991e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -4.316 sec. to -3.316 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.27315 ( )
Epeak [keV] : 9568.00 ( )
Norm@50keV : 5.39512E-05 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.37 using 59 PHA bins.
# Reduced chi-squared = 1.167 for 56 degrees of freedom
# Null hypothesis probability = 1.833258e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 5.68617e-08 ( -2.1413e-08 2.06666e-08 ) ergs/cm2
Time-resolved spectra
