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 -7.560 sec. to 25.440 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.36995 ( -0.0711243 0.0714256 )
Norm@50keV : 1.62356E-02 ( -0.000692201 0.000691907 )
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#Fit statistic : Chi-Squared = 63.34 using 59 PHA bins.
# Reduced chi-squared = 1.111 for 57 degrees of freedom
# Null hypothesis probability = 2.628274e-01
Photon flux (15-150 keV) in 33 sec: 1.96417 ( -0.09165 0.09192 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.21044e-06 ( -2.27975e-07 2.28375e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -7.560 sec. to 25.440 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.71363 ( -0.311401 0.334615 )
Epeak [keV] : 113.155 ( -20.0623 49.2456 )
Norm@50keV : 3.17596E-02 ( -0.00846151 0.0124245 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.46 using 59 PHA bins.
# Reduced chi-squared = 0.8832 for 56 degrees of freedom
# Null hypothesis probability = 7.190460e-01
Photon flux (15-150 keV) in 33 sec: 1.90137 ( -0.09546 0.096 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.1052e-06 ( -2.37161e-07 2.36679e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 5.440 sec. to 6.440 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.31935 ( -0.142389 0.14162 )
Norm@50keV : 6.22358E-02 ( -0.00543228 0.00543215 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.38 using 59 PHA bins.
# Reduced chi-squared = 1.270 for 57 degrees of freedom
# Null hypothesis probability = 8.241555e-02
Photon flux (15-150 keV) in 1 sec: 7.45209 ( -0.68277 0.68454 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.12224e-07 ( -5.68315e-08 5.70285e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 5.440 sec. to 6.440 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.470178 ( -0.623136 0.725412 )
Epeak [keV] : 107.034 ( -24.5538 120.997 )
Norm@50keV : 0.145660 ( -0.0663435 0.142881 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.74 using 59 PHA bins.
# Reduced chi-squared = 1.192 for 56 degrees of freedom
# Null hypothesis probability = 1.541307e-01
Photon flux (15-150 keV) in 1 sec: 7.20845 ( -0.70622 0.70791 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.05006e-07 ( -5.83174e-08 5.82329e-08 ) ergs/cm2
Time-resolved spectra
