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 -0.060 sec. to 12.136 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.46017 ( -0.088904 0.0887968 )
Norm@50keV : 1.01740E-02 ( -0.000521646 0.000521084 )
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#Fit statistic : Chi-Squared = 47.71 using 59 PHA bins.
# Reduced chi-squared = 0.8370 for 57 degrees of freedom
# Null hypothesis probability = 8.048811e-01
Photon flux (15-150 keV) in 12.2 sec: 1.25703 ( -0.0663 0.06639 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.18571e-06 ( -6.60952e-08 6.63892e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.060 sec. to 12.136 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.0645 ( -0.339258 0.367801 )
Epeak [keV] : 121.704 ( -35.901 338.3 )
Norm@50keV : 1.59367E-02 ( -0.00497421 0.0079873 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.67 using 59 PHA bins.
# Reduced chi-squared = 0.7799 for 56 degrees of freedom
# Null hypothesis probability = 8.846982e-01
Photon flux (15-150 keV) in 12.2 sec: 1.23303 ( -0.06931 0.06934 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.15319e-06 ( -7.23009e-08 7.21624e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 4.100 sec. to 5.100 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.11354 ( -0.105636 0.106849 )
Norm@50keV : 3.37020E-02 ( -0.00220365 0.00220299 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.17 using 59 PHA bins.
# Reduced chi-squared = 1.056 for 57 degrees of freedom
# Null hypothesis probability = 3.618685e-01
Photon flux (15-150 keV) in 1 sec: 3.91449 ( -0.26194 0.2622 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.50889e-07 ( -2.50073e-08 2.51215e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 4.100 sec. to 5.100 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.38113 ( -0.443405 0.495822 )
Epeak [keV] : 120.862 ( -28.672 97.1128 )
Norm@50keV : 7.45241E-02 ( -0.0278329 0.050427 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.67 using 59 PHA bins.
# Reduced chi-squared = 0.9227 for 56 degrees of freedom
# Null hypothesis probability = 6.392181e-01
Photon flux (15-150 keV) in 1 sec: 3.83017 ( -0.26749 0.26745 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.38626e-07 ( -2.68519e-08 2.67247e-08 ) ergs/cm2
Time-resolved spectra
