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 -15.144 sec. to 80.856 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.81314 ( -0.0514679 0.0512392 )
Norm@50keV : 1.02998E-02 ( -0.000266947 0.000266464 )
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#Fit statistic : Chi-Squared = 57.82 using 59 PHA bins.
# Reduced chi-squared = 1.014 for 57 degrees of freedom
# Null hypothesis probability = 4.447247e-01
Photon flux (15-150 keV) in 96 sec: 1.42667 ( -0.04185 0.04205 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.10042e-06 ( -2.3863e-07 2.38817e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -15.144 sec. to 80.856 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.81342 ( -0.050871 0.0539837 )
Epeak [keV] : 9999.36 ( -9999.35 -9999.36 )
Norm@50keV : 1.03066E-02 ( -0.000264628 0.00180835 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.83 using 59 PHA bins.
# Reduced chi-squared = 1.033 for 56 degrees of freedom
# Null hypothesis probability = 4.074460e-01
Photon flux (15-150 keV) in 96 sec: 1.32057 ( -0.06894 0.05806 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.12896e-06 ( -3.64375e-07 2.84762e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 40.356 sec. to 41.356 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.7667 ( -0.0879893 0.0869094 )
Norm@50keV : 5.53066E-02 ( -0.0027927 0.00277806 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.23 using 59 PHA bins.
# Reduced chi-squared = 0.8111 for 57 degrees of freedom
# Null hypothesis probability = 8.452983e-01
Photon flux (15-150 keV) in 1 sec: 7.52532 ( -0.37367 0.37442 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.09953e-07 ( -2.64491e-08 2.65844e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 40.356 sec. to 41.356 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.54347 ( -0.266735 0.354383 )
Epeak [keV] : 99.7208 ( -34.9559 -99.7223 )
Norm@50keV : 7.20328E-02 ( -0.0186493 0.0366522 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.90 using 59 PHA bins.
# Reduced chi-squared = 0.8018 for 56 degrees of freedom
# Null hypothesis probability = 8.561720e-01
Photon flux (15-150 keV) in 1 sec: 7.43287 ( -0.39678 0.39711 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.0106e-07 ( -2.96921e-08 2.95434e-08 ) ergs/cm2
Time-resolved spectra
