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 -35.208 sec. to 41.328 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.66934 ( -0.051889 0.0517362 )
Norm@50keV : 1.26452E-02 ( -0.000358263 0.000358212 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.46 using 59 PHA bins.
# Reduced chi-squared = 1.026 for 57 degrees of freedom
# Null hypothesis probability = 4.213783e-01
Photon flux (15-150 keV) in 76.54 sec: 1.66191 ( -0.05345 0.05365 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.98603e-06 ( -2.60965e-07 2.61136e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -35.208 sec. to 41.328 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.27732 ( -0.214759 0.22513 )
Epeak [keV] : 101.244 ( -18.4256 54.6152 )
Norm@50keV : 1.91453E-02 ( -0.00380462 0.00501101 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.44 using 59 PHA bins.
# Reduced chi-squared = 0.8649 for 56 degrees of freedom
# Null hypothesis probability = 7.536400e-01
Photon flux (15-150 keV) in 76.54 sec: 1.61335 ( -0.05867 0.05902 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.78901e-06 ( -2.83735e-07 2.82684e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 6.176 sec. to 7.176 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.16034 ( -0.105368 0.106408 )
Norm@50keV : 6.18777E-02 ( -0.00408334 0.0040795 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.00 using 59 PHA bins.
# Reduced chi-squared = 1.105 for 57 degrees of freedom
# Null hypothesis probability = 2.723710e-01
Photon flux (15-150 keV) in 1 sec: 0.206518 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 6.35097e-07 ( -4.39847e-08 4.41066e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 6.176 sec. to 7.176 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.358233 ( -0.459799 0.515808 )
Epeak [keV] : 118.837 ( -25.5438 78.9416 )
Norm@50keV : 0.140621 ( -0.0516324 0.0919689 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.46 using 59 PHA bins.
# Reduced chi-squared = 0.9547 for 56 degrees of freedom
# Null hypothesis probability = 5.715000e-01
Photon flux (15-150 keV) in 1 sec: 7.04655 ( -0.50669 0.50757 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.2273e-07 ( -4.57643e-08 4.56139e-08 ) ergs/cm2
Time-resolved spectra
