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 -0.104 sec. to 21.816 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -2.27024 ( -0.0658492 0.0648655 )
Norm@50keV : 3.08648E-02 ( -0.00109266 0.0010864 )
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#Fit statistic : Chi-Squared = 42.92 using 59 PHA bins.
# Reduced chi-squared = 0.7530 for 57 degrees of freedom
# Null hypothesis probability = 9.165109e-01
Photon flux (15-150 keV) in 21.92 sec: 5.30663 ( -0.19898 0.20041 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.43251e-06 ( -2.05774e-07 2.05845e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.104 sec. to 21.816 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.99632 ( -0.00088396 0.169291 )
Epeak [keV] : 0.674262 ( -0.140623 0.223427 )
Norm@50keV : 4.20776E-02 ( -0.00281458 0.00305841 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 42.31 using 59 PHA bins.
# Reduced chi-squared = 0.7556 for 56 degrees of freedom
# Null hypothesis probability = 9.118960e-01
Photon flux (15-150 keV) in 21.92 sec: 5.14952 ( -0.15959 0.18094 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.39957e-06 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 8.044 sec. to 9.044 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.7972 ( -0.106893 0.105164 )
Norm@50keV : 0.103216 ( -0.00625877 0.00623383 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.25 using 59 PHA bins.
# Reduced chi-squared = 0.6534 for 57 degrees of freedom
# Null hypothesis probability = 9.801441e-01
Photon flux (15-150 keV) in 1 sec: 14.2082 ( -0.9114 0.9146 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.50452e-07 ( -5.84209e-08 5.85453e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 8.044 sec. to 9.044 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.29932 ( -0.107408 0.149155 )
Epeak [keV] : 116.169 ( -9999.35 -9999.36 )
Norm@50keV : 5.77570E-02 ( -0.0226602 0.0223046 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 36.69 using 59 PHA bins.
# Reduced chi-squared = 0.6552 for 56 degrees of freedom
# Null hypothesis probability = 9.785692e-01
Photon flux (15-150 keV) in 1 sec: 12.7287 ( -1.0218 0.9025 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.52752e-07 ( -7.44174e-08 6.98344e-08 ) ergs/cm2
Time-resolved spectra
