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 -0.692 sec. to 4.144 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.30595 ( -0.0603959 0.0604793 )
Norm@50keV : 2.22008E-02 ( -0.000754764 0.000754738 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.07 using 59 PHA bins.
# Reduced chi-squared = 0.9661 for 57 degrees of freedom
# Null hypothesis probability = 5.479774e-01
Photon flux (15-150 keV) in 4.836 sec: 2.65156 ( -0.09573 0.09592 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.05954e-06 ( -3.87253e-08 3.88001e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.692 sec. to 4.144 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.749432 ( -0.255998 0.271344 )
Epeak [keV] : 126.124 ( -23.965 58.1178 )
Norm@50keV : 3.95934E-02 ( -0.00902869 0.0124586 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.42 using 59 PHA bins.
# Reduced chi-squared = 0.7217 for 56 degrees of freedom
# Null hypothesis probability = 9.420539e-01
Photon flux (15-150 keV) in 4.836 sec: 2.56941 ( -0.10187 0.10222 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.02867e-06 ( -4.1786e-08 4.16561e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.116 sec. to 0.884 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.10246 ( -0.063535 0.0638076 )
Norm@50keV : 5.62419E-02 ( -0.0021199 0.00211917 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.27 using 59 PHA bins.
# Reduced chi-squared = 1.198 for 57 degrees of freedom
# Null hypothesis probability = 1.458889e-01
Photon flux (15-150 keV) in 1 sec: 0.353026 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 5.87625e-07 ( -2.40782e-08 2.41194e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.116 sec. to 0.884 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.564481 ( -0.259274 0.275325 )
Epeak [keV] : 153.929 ( -33.3107 85.7706 )
Norm@50keV : 9.76673E-02 ( -0.0222018 0.0305329 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.91 using 59 PHA bins.
# Reduced chi-squared = 0.9805 for 56 degrees of freedom
# Null hypothesis probability = 5.162968e-01
Photon flux (15-150 keV) in 1 sec: 6.39582 ( -0.25979 0.25997 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.76116e-07 ( -2.52068e-08 2.51408e-08 ) ergs/cm2
Time-resolved spectra
