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 -15.560 sec. to 32.440 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.26518 ( -0.212758 0.21845 )
Norm@50keV : 2.16446E-03 ( -0.000269055 0.000268435 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.27 using 59 PHA bins.
# Reduced chi-squared = 1.057 for 57 degrees of freedom
# Null hypothesis probability = 3.585407e-01
Photon flux (15-150 keV) in 48 sec: 0.256645 ( -0.034206 0.034416 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.03579e-06 ( -1.33507e-07 1.33877e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -15.560 sec. to 32.440 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.02328 ( -0.43137 0.882054 )
Epeak [keV] : 231.912 ( -231.713 -231.713 )
Norm@50keV : 2.77884E-03 ( -0.00277964 0.00378573 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.98 using 59 PHA bins.
# Reduced chi-squared = 1.071 for 56 degrees of freedom
# Null hypothesis probability = 3.336318e-01
Photon flux (15-150 keV) in 48 sec: 0.253809 ( -0.035395 0.035508 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.0267e-06 ( -1.37779e-07 1.37031e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 7.940 sec. to 8.940 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.67266 ( -0.783923 0.793898 )
Norm@50keV : 3.83039E-03 ( -0.00190678 0.00187069 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.96 using 59 PHA bins.
# Reduced chi-squared = 1.052 for 57 degrees of freedom
# Null hypothesis probability = 3.687939e-01
Photon flux (15-150 keV) in 1 sec: 0.503893 ( -0.241927 0.244635 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.55631e-08 ( -1.7513e-08 1.85061e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 7.940 sec. to 8.940 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 9.96989 ( )
Epeak [keV] : 34.2065 ( )
Norm@50keV : 1.17708E+05 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.64 using 59 PHA bins.
# Reduced chi-squared = 0.9757 for 56 degrees of freedom
# Null hypothesis probability = 5.264812e-01
Photon flux (15-150 keV) in 1 sec: 0.428128 ( -0.157094 0.233839 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.18937e-08 ( -7.96085e-09 1.21001e-08 ) ergs/cm2
Time-resolved spectra
