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 -1.436 sec. to 5.704 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.43252 ( -0.243464 0.223304 )
Norm@50keV : 5.18734E-03 ( -0.000929417 0.000920944 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.22 using 59 PHA bins.
# Reduced chi-squared = 0.8810 for 57 degrees of freedom
# Null hypothesis probability = 7.254129e-01
Photon flux (15-150 keV) in 7.14 sec: 0.978500 ( -0.112169 0.11217 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.6414e-07 ( -5.03651e-08 5.18551e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.436 sec. to 5.704 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.986438 ( -0.898092 1.3295 )
Epeak [keV] : 25.5934 ( )
Norm@50keV : 4.15770E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.14 using 59 PHA bins.
# Reduced chi-squared = 0.7882 for 56 degrees of freedom
# Null hypothesis probability = 8.742817e-01
Photon flux (15-150 keV) in 7.14 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 3.344 sec. to 4.344 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.25497 ( -0.392635 0.340579 )
Norm@50keV : 8.52384E-03 ( -0.0024608 0.00240409 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.42 using 59 PHA bins.
# Reduced chi-squared = 1.130 for 57 degrees of freedom
# Null hypothesis probability = 2.329904e-01
Photon flux (15-150 keV) in 1 sec: 1.45337 ( -0.3045 0.30449 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.08202e-08 ( -1.97457e-08 2.04659e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 3.344 sec. to 4.344 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.498128 ( -1.45459 1.93017 )
Epeak [keV] : 35.0120 ( )
Norm@50keV : 9.26196E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.97 using 59 PHA bins.
# Reduced chi-squared = 1.071 for 56 degrees of freedom
# Null hypothesis probability = 3.338199e-01
Photon flux (15-150 keV) in 1 sec: 1.43701 ( -0.3007 0.30041 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.65086e-08 ( -1.84536e-08 1.92064e-08 ) ergs/cm2
Time-resolved spectra
