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 -0.072 sec. to 2.832 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.3591 ( -0.279249 0.279662 )
Norm@50keV : 6.13270E-03 ( -0.000953225 0.000947467 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.88 using 59 PHA bins.
# Reduced chi-squared = 0.9453 for 57 degrees of freedom
# Null hypothesis probability = 5.928368e-01
Photon flux (15-150 keV) in 2.904 sec: 0.740221 ( -0.114773 0.114983 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.73611e-07 ( -3.03468e-08 3.08155e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.072 sec. to 2.832 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.35588 ( -1.37906 0.877069 )
Epeak [keV] : 1.00000E+04 ( -10000 -10000 )
Norm@50keV : 6.15607E-03 ( -0.000959513 -0.00615621 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.88 using 59 PHA bins.
# Reduced chi-squared = 0.9622 for 56 degrees of freedom
# Null hypothesis probability = 5.553756e-01
Photon flux (15-150 keV) in 2.904 sec: 0.744662 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.74228e-07 ( -3.25384e-08 2.22381e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.086 sec. to 0.914 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.44142 ( -0.280317 0.280249 )
Norm@50keV : 1.02726E-02 ( -0.0017346 0.00171633 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.08 using 59 PHA bins.
# Reduced chi-squared = 1.142 for 57 degrees of freedom
# Null hypothesis probability = 2.160607e-01
Photon flux (15-150 keV) in 1 sec: 1.26331 ( -0.20658 0.20675 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.84714e-08 ( -1.83276e-08 1.86699e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.086 sec. to 0.914 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.28493 ( )
Epeak [keV] : 215.052 ( )
Norm@50keV : 1.24761E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.00 using 59 PHA bins.
# Reduced chi-squared = 1.161 for 56 degrees of freedom
# Null hypothesis probability = 1.918498e-01
Photon flux (15-150 keV) in 1 sec: 1.25675 ( -0.21007 0.21023 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.69483e-08 ( -2.0786e-08 1.98052e-08 ) ergs/cm2
Time-resolved spectra
