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 -29.136 sec. to 100.276 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.50698 ( -0.0509578 0.0509565 )
Norm@50keV : 1.17873E-02 ( -0.000332415 0.000332411 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.74 using 59 PHA bins.
# Reduced chi-squared = 0.9428 for 57 degrees of freedom
# Null hypothesis probability = 5.981293e-01
Photon flux (15-150 keV) in 129.4 sec: 1.47433 ( -0.04657 0.04672 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.44549e-05 ( -4.22087e-07 4.22763e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -29.136 sec. to 100.276 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.13231 ( -0.207276 0.216844 )
Epeak [keV] : 130.335 ( -28.0953 87.4448 )
Norm@50keV : 1.73864E-02 ( -0.0032848 0.00424935 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.91 using 59 PHA bins.
# Reduced chi-squared = 0.7841 for 56 degrees of freedom
# Null hypothesis probability = 8.795263e-01
Photon flux (15-150 keV) in 129.4 sec: 1.43706 ( -0.05026 0.05049 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.41838e-05 ( -4.51145e-07 4.49912e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.404 sec. to 2.404 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.39511 ( -0.169455 0.169085 )
Norm@50keV : 5.80484E-02 ( -0.00587169 0.0058638 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.82 using 59 PHA bins.
# Reduced chi-squared = 0.8916 for 57 degrees of freedom
# Null hypothesis probability = 7.047841e-01
Photon flux (15-150 keV) in 1 sec: 7.06154 ( -0.74067 0.74225 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.61539e-07 ( -6.13317e-08 6.15642e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.404 sec. to 2.404 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.0093 ( -0.471311 0.760931 )
Epeak [keV] : 138.510 ( )
Norm@50keV : 8.88551E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.85 using 59 PHA bins.
# Reduced chi-squared = 0.8903 for 56 degrees of freedom
# Null hypothesis probability = 7.053055e-01
Photon flux (15-150 keV) in 1 sec: 6.96672 ( -0.76005 0.76018 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.52548e-07 ( -6.44467e-08 6.3905e-08 ) ergs/cm2
Time-resolved spectra
