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 -0.828 sec. to 84.320 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.25484 ( -0.0529935 0.0525186 )
Norm@50keV : 1.29244E-02 ( -0.000350335 0.000349037 )
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#Fit statistic : Chi-Squared = 58.03 using 59 PHA bins.
# Reduced chi-squared = 1.018 for 57 degrees of freedom
# Null hypothesis probability = 4.370189e-01
Photon flux (15-150 keV) in 85.15 sec: 2.20354 ( -0.06683 0.06733 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.04362e-05 ( -2.59359e-07 2.59594e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.828 sec. to 84.320 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.9936 ( 1.9936 0.194221 )
Epeak [keV] : 1.18857 ( -0.210851 0.311669 )
Norm@50keV : 1.74665E-02 ( -0.000827872 0.0010213 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.51 using 59 PHA bins.
# Reduced chi-squared = 0.9735 for 56 degrees of freedom
# Null hypothesis probability = 5.312836e-01
Photon flux (15-150 keV) in 85.15 sec: 2.14664 ( -0.0559 0.056 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.136 sec. to 0.864 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.87572 ( -0.127486 0.123328 )
Norm@50keV : 4.01073E-02 ( -0.00326792 0.00323552 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.57 using 59 PHA bins.
# Reduced chi-squared = 0.8522 for 57 degrees of freedom
# Null hypothesis probability = 7.789149e-01
Photon flux (15-150 keV) in 1 sec: 5.69774 ( -0.42911 0.42973 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.68765e-07 ( -2.9796e-08 3.00027e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.136 sec. to 0.864 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.804774 ( -0.559719 0.636655 )
Epeak [keV] : 53.5219 ( -7.37517 11.8432 )
Norm@50keV : 0.145358 ( -0.070172 0.165065 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 36.80 using 59 PHA bins.
# Reduced chi-squared = 0.6571 for 56 degrees of freedom
# Null hypothesis probability = 9.778870e-01
Photon flux (15-150 keV) in 1 sec: 5.46529 ( -0.44355 0.44479 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.48739e-07 ( -3.13148e-08 3.17131e-08 ) ergs/cm2
Time-resolved spectra
