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 -0.824 sec. to 59.864 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.33596 ( -0.248194 0.248265 )
Norm@50keV : 1.35455E-03 ( -0.000181794 0.000181193 )
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#Fit statistic : Chi-Squared 60.49 using 59 bins.
Reduced chi-squared = 1.06123
# Null hypothesis probability of 3.51e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 60.69 sec: 0.162723 ( -0.022084 0.022151 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.05557e-07 ( -1.2198e-07 1.23789e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.824 sec. to 59.864 sec.
Spectral model in the cutoff power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.33242 ( -1.65878 0.865301 )
Epeak [keV] : 9998.49 ( -9998.56 -9998.56 )
Norm@50keV : 1.35993E-03 ( -0.00119107 0.00225686 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 60.49 using 59 bins.
Reduced chi-squared = 1.08018
# Null hypothesis probability of 3.17e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 60.69 sec: 0.162943 ( -0.023493 0.022049 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.06801e-07 ( -1.33208e-07 9.99067e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.008 sec. to 2.008 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.10294 ( -0.35461 0.370323 )
Norm@50keV : 7.48136E-03 ( -0.00153728 0.00153709 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 63.48 using 59 bins.
Reduced chi-squared = 1.11368
# Null hypothesis probability of 2.59e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.868036 ( -0.18109 0.181574 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.81538e-08 ( -1.79672e-08 1.83468e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.008 sec. to 2.008 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.619317 ( 0.619383 2.05223 )
Epeak [keV] : 144.010 ( -144.118 -144.118 )
Norm@50keV : 1.31081E-02 ( -0.00701922 0.0814037 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 63.16 using 59 bins.
Reduced chi-squared = 1.12786
# Null hypothesis probability of 2.38e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.850379 ( -0.190496 0.188801 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.45865e-08 ( -2.23276e-08 2.07721e-08 ) ergs/cm2
Time-resolved spectra
