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 -9.996 sec. to 25.704 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.95058 ( -0.122369 0.119787 )
Norm@50keV : 7.16879E-03 ( -0.000514595 0.000508838 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.71 using 59 PHA bins.
# Reduced chi-squared = 1.276 for 57 degrees of freedom
# Null hypothesis probability = 7.843826e-02
Photon flux (15-150 keV) in 35.7 sec: 1.05168 ( -0.071412 0.07168 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.35564e-06 ( -1.63849e-07 1.64757e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -9.996 sec. to 25.704 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.01065 ( -0.013823 0.446129 )
Epeak [keV] : 8.12603 ( )
Norm@50keV : 6.65484E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.64 using 59 PHA bins.
# Reduced chi-squared = 1.297 for 56 degrees of freedom
# Null hypothesis probability = 6.676483e-02
Photon flux (15-150 keV) in 35.7 sec: 1.03062 ( -0.133493 0.10102 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.36946e-06 ( -1.83818e-07 1.57155e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.580 sec. to 1.580 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.84979 ( -0.207154 0.201656 )
Norm@50keV : 2.78208E-02 ( -0.00355849 0.00349897 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.43 using 59 PHA bins.
# Reduced chi-squared = 1.183 for 57 degrees of freedom
# Null hypothesis probability = 1.625325e-01
Photon flux (15-150 keV) in 1 sec: 3.91038 ( -0.47119 0.47223 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.55847e-07 ( -3.25669e-08 3.2782e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.580 sec. to 1.580 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.85523 ( -0.705641 0.712774 )
Epeak [keV] : 9999.36 ( )
Norm@50keV : 2.77527E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.43 using 59 PHA bins.
# Reduced chi-squared = 1.204 for 56 degrees of freedom
# Null hypothesis probability = 1.409466e-01
Photon flux (15-150 keV) in 1 sec: 3.58162 ( -0.77133 0.79692 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.56478e-07 ( -3.32853e-08 2.65699e-08 ) ergs/cm2
Time-resolved spectra
