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 35.016 sec. to 89.992 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.90444 ( -0.279651 0.261448 )
Norm@50keV : 1.70957E-03 ( -0.000302451 0.00029196 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.31 using 59 PHA bins.
# Reduced chi-squared = 1.041 for 57 degrees of freedom
# Null hypothesis probability = 3.913477e-01
Photon flux (15-150 keV) in 54.98 sec: 0.245821 ( -0.034867 0.034881 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.64319e-07 ( -1.46566e-07 1.50117e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 35.016 sec. to 89.992 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.7929 ( -0.605017 1.0983 )
Epeak [keV] : 81.6703 ( -81.6277 -81.6432 )
Norm@50keV : 1.97523E-03 ( -0.00197545 0.00612922 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.27 using 59 PHA bins.
# Reduced chi-squared = 1.058 for 56 degrees of freedom
# Null hypothesis probability = 3.572749e-01
Photon flux (15-150 keV) in 54.98 sec: 0.244801 ( -0.035889 0.035612 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.55016e-07 ( -1.63942e-07 1.41547e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 37.916 sec. to 38.916 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.75295 ( -0.425256 0.405511 )
Norm@50keV : 8.66280E-03 ( -0.00234495 0.00227051 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.65 using 59 PHA bins.
# Reduced chi-squared = 0.8535 for 57 degrees of freedom
# Null hypothesis probability = 7.766305e-01
Photon flux (15-150 keV) in 1 sec: 1.17269 ( -0.280722 0.28101 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.99337e-08 ( -2.16738e-08 2.2372e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 37.916 sec. to 38.916 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.09293 ( -1.30739 4.67375 )
Epeak [keV] : 57.0211 ( )
Norm@50keV : 2.10883E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.28 using 59 PHA bins.
# Reduced chi-squared = 0.8621 for 56 degrees of freedom
# Null hypothesis probability = 7.587077e-01
Photon flux (15-150 keV) in 1 sec: 1.14867 ( -0.299354 0.28955 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.3731e-08 ( -2.73628e-08 2.65642e-08 ) ergs/cm2
Time-resolved spectra
