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 -56.472 sec. to 229.960 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.12509 ( -0.0606083 0.0612853 )
Norm@50keV : 5.26232E-03 ( -0.000181201 0.000180484 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.15 using 59 PHA bins.
# Reduced chi-squared = 1.073 for 57 degrees of freedom
# Null hypothesis probability = 3.292939e-01
Photon flux (15-150 keV) in 286.4 sec: 0.611964 ( -0.022606 0.022756 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.56352e-05 ( -5.19661e-07 5.20048e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -56.472 sec. to 229.960 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.12377 ( -0.0580065 0.0676704 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 5.28440E-03 ( -0.000172562 0.000646778 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.26 using 59 PHA bins.
# Reduced chi-squared = 1.094 for 56 degrees of freedom
# Null hypothesis probability = 2.929506e-01
Photon flux (15-150 keV) in 286.4 sec: 0.616790 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.56868e-05 ( -5.74026e-07 4.65864e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -4.084 sec. to -3.084 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.933374 ( -0.214783 0.222595 )
Norm@50keV : 3.86648E-02 ( -0.00519359 0.0051176 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 38.73 using 59 PHA bins.
# Reduced chi-squared = 0.6794 for 57 degrees of freedom
# Null hypothesis probability = 9.695584e-01
Photon flux (15-150 keV) in 1 sec: 0.154033 ( -0.01891 0.123661 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.2847e-07 ( -5.56837e-08 5.57247e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -4.084 sec. to -3.084 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.629182 ( -0.488396 0.947092 )
Epeak [keV] : 291.553 ( -291.553 -291.553 )
Norm@50keV : 5.10521E-02 ( -0.0167197 0.0635603 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 38.32 using 59 PHA bins.
# Reduced chi-squared = 0.6843 for 56 degrees of freedom
# Null hypothesis probability = 9.658834e-01
Photon flux (15-150 keV) in 1 sec: 0.328211 ( -0.328211 -0.302782 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.28046e-07 ( -5.63225e-08 5.6171e-08 ) ergs/cm2
Time-resolved spectra
