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 -1.208 sec. to 26.312 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -2.0096 ( -0.217587 0.208216 )
Norm@50keV : 4.35423E-03 ( -0.000572253 0.00055815 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.32 using 59 PHA bins.
# Reduced chi-squared = 0.7075 for 57 degrees of freedom
# Null hypothesis probability = 9.537863e-01
Photon flux (15-150 keV) in 27.52 sec: 0.656082 ( -0.075132 0.075411 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.10581e-06 ( -1.35992e-07 1.3753e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.208 sec. to 26.312 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.98578 ( -0.107244 0.875378 )
Epeak [keV] : 26.9937 ( -24.7657 -27.0027 )
Norm@50keV : 4.48744E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.32 using 59 PHA bins.
# Reduced chi-squared = 0.7200 for 56 degrees of freedom
# Null hypothesis probability = 9.433133e-01
Photon flux (15-150 keV) in 27.52 sec: 0.655345 ( -0.078908 0.073835 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.10354e-06 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 2.484 sec. to 3.484 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.25334 ( -0.449191 0.393492 )
Norm@50keV : 1.18941E-02 ( -0.00334767 0.00314462 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.50 using 59 PHA bins.
# Reduced chi-squared = 0.7983 for 57 degrees of freedom
# Null hypothesis probability = 8.633860e-01
Photon flux (15-150 keV) in 1 sec: 2.02622 ( -0.40635 0.40765 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.12766e-07 ( -2.56456e-08 2.63445e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.484 sec. to 3.484 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.48865 ( -0.254834 1.55376 )
Epeak [keV] : 189.912 ( )
Norm@50keV : 8.94737E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.34 using 59 PHA bins.
# Reduced chi-squared = 0.8097 for 56 degrees of freedom
# Null hypothesis probability = 8.449202e-01
Photon flux (15-150 keV) in 1 sec: 1.99450 ( -0.3957 0.39777 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Time-resolved spectra
