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 -49.224 sec. to 139.444 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.10782 ( -0.051019 0.0513474 )
Norm@50keV : 2.97314E-03 ( -8.14167e-05 8.12379e-05 )
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#Fit statistic : Chi-Squared = 58.05 using 59 PHA bins.
# Reduced chi-squared = 1.018 for 57 degrees of freedom
# Null hypothesis probability = 4.362448e-01
Photon flux (15-150 keV) in 188.7 sec: 0.345130 ( -0.009963 0.009984 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.85183e-06 ( -1.67075e-07 1.67272e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -49.224 sec. to 139.444 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.00833 ( -0.119691 0.205215 )
Epeak [keV] : 587.200 ( -587.204 -587.204 )
Norm@50keV : 3.28004E-03 ( -0.000210299 0.000712498 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.32 using 59 PHA bins.
# Reduced chi-squared = 1.024 for 56 degrees of freedom
# Null hypothesis probability = 4.259435e-01
Photon flux (15-150 keV) in 188.7 sec: 0.342957 ( -0.010799 0.00967 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.82011e-06 ( -1.78907e-07 1.69407e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 8.924 sec. to 9.924 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.599732 ( -0.128736 0.132956 )
Norm@50keV : 1.66179E-02 ( -0.00130102 0.00128533 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.27 using 59 PHA bins.
# Reduced chi-squared = 1.198 for 57 degrees of freedom
# Null hypothesis probability = 1.457640e-01
Photon flux (15-150 keV) in 1 sec: 1.94028 ( -0.14064 0.14081 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.12559e-07 ( -1.62501e-08 1.63063e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 8.924 sec. to 9.924 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.108442 ( -0.457434 0.660537 )
Epeak [keV] : 249.337 ( -105.124 -249.319 )
Norm@50keV : 2.57798E-02 ( -0.00894996 0.0190861 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.10 using 59 PHA bins.
# Reduced chi-squared = 1.180 for 56 degrees of freedom
# Null hypothesis probability = 1.674709e-01
Photon flux (15-150 keV) in 1 sec: 1.90942 ( -0.14571 0.14527 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.10252e-07 ( -1.68415e-08 1.67606e-08 ) ergs/cm2
Time-resolved spectra
