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 -0.512 sec. to 6.448 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.07279 ( -0.555557 0.478002 )
Norm@50keV : 1.96611E-03 ( -0.00073225 0.000701504 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 78.01 using 59 bins.
Reduced chi-squared = 1.3686
# Null hypothesis probability of 3.38e-02 with 57 degrees of freedom
Photon flux (15-150 keV) in 6.96 sec: 0.305256 ( -0.078631 0.078658 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.26849e-07 ( -4.09325e-08 4.41675e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.512 sec. to 6.448 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.93682 ( )
Epeak [keV] : 17.0736 ( )
Norm@50keV : 2.40071E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared 77.97 using 59 bins.
Reduced chi-squared = 1.39232
# Null hypothesis probability of 2.78e-02 with 56 degrees of freedom
Photon flux (15-150 keV) in 6.96 sec: 0.305108 ( -0.078218 0.078862 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.23589e-07 ( -4.96147e-08 4.02435e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.252 sec. to 0.748 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.82777 ( -0.562772 0.513836 )
Norm@50keV : 4.87108E-03 ( -0.00185346 0.00179538 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 64.15 using 59 bins.
Reduced chi-squared = 1.12544
# Null hypothesis probability of 2.40e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.678622 ( -0.213763 0.213766 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.48208e-08 ( -1.64253e-08 1.7524e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.252 sec. to 0.748 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 9.61081 ( )
Epeak [keV] : 27.8381 ( )
Norm@50keV : 8.46582E+05 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared 61.69 using 59 bins.
Reduced chi-squared = 1.10161
# Null hypothesis probability of 2.80e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.585599 ( -0.180393 0.207004 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.49086e-08 ( -7.9929e-09 2.66772e-08 ) ergs/cm2
Time-resolved spectra
