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 -1.924 sec. to 20.952 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.44065 ( -0.14499 0.144909 )
Norm@50keV : 5.67314E-03 ( -0.000491298 0.000490672 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 71.61 using 59 bins.
Reduced chi-squared = 1.25632
# Null hypothesis probability of 9.22e-02 with 57 degrees of freedom
Photon flux (15-150 keV) in 22.88 sec: 0.697542 ( -0.062145 0.062281 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.24442e-06 ( -1.16322e-07 1.17171e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.924 sec. to 20.952 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.862411 ( -0.554909 0.63519 )
Epeak [keV] : 101.319 ( -29.9122 627.034 )
Norm@50keV : 1.09621E-02 ( -0.00503154 0.0112204 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 68.41 using 59 bins.
Reduced chi-squared = 1.22161
# Null hypothesis probability of 1.23e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 22.88 sec: 0.681656 ( -0.063931 0.064046 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.20115e-06 ( -1.2551e-07 1.25135e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.024 sec. to 1.024 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.30563 ( -0.203283 0.202438 )
Norm@50keV : 2.37059E-02 ( -0.0027357 0.00272871 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 78.12 using 59 bins.
Reduced chi-squared = 1.37053
# Null hypothesis probability of 3.31e-02 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 2.83116 ( -0.33319 0.33388 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.33965e-07 ( -3.00919e-08 3.02941e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.024 sec. to 1.024 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.02836 ( -0.00389424 0.0357975 )
Epeak [keV] : 10.8513 ( )
Norm@50keV : 7.43198E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared 76.12 using 59 bins.
Reduced chi-squared = 1.35929
# Null hypothesis probability of 3.81e-02 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 2.83208 ( -0.34126 0.3319 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.34062e-07 ( -3.13544e-08 3.02397e-08 ) ergs/cm2
Time-resolved spectra
