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 -0.004 sec. to 89.392 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.54703 ( -0.274337 0.27099 )
Norm@50keV : 1.29511E-03 ( -0.000193833 0.000191599 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.39 using 59 PHA bins.
# Reduced chi-squared = 1.147 for 57 degrees of freedom
# Null hypothesis probability = 2.085161e-01
Photon flux (15-150 keV) in 89.4 sec: 0.163817 ( -0.024465 0.024569 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.09061e-06 ( -1.76248e-07 1.77942e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.004 sec. to 89.392 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.55741 ( -0.264535 0.28487 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 1.29021E-03 ( -0.000191476 0.00104206 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.40 using 59 PHA bins.
# Reduced chi-squared = 1.168 for 56 degrees of freedom
# Null hypothesis probability = 1.826505e-01
Photon flux (15-150 keV) in 89.4 sec: 0.163829 ( -0.024529 0.024529 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.09761e-06 ( -1.83459e-07 1.70474e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.230 sec. to 0.770 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.756516 ( -0.177088 0.185773 )
Norm@50keV : 2.43909E-02 ( -0.00266678 0.00262067 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.29 using 59 PHA bins.
# Reduced chi-squared = 0.8647 for 57 degrees of freedom
# Null hypothesis probability = 7.563158e-01
Photon flux (15-150 keV) in 1 sec: 2.80873 ( -0.293 0.29405 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.90402e-07 ( -3.00805e-08 3.01364e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.230 sec. to 0.770 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.478131 ( -0.358612 0.833967 )
Epeak [keV] : 346.187 ( -346.187 -346.187 )
Norm@50keV : 3.15564E-02 ( -0.0093266 0.0337221 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.86 using 59 PHA bins.
# Reduced chi-squared = 0.8724 for 56 degrees of freedom
# Null hypothesis probability = 7.396927e-01
Photon flux (15-150 keV) in 1 sec: 2.78155 ( -0.30088 0.30194 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.88642e-07 ( -3.08971e-08 3.06514e-08 ) ergs/cm2
Time-resolved spectra
