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 -7.040 sec. to 21.120 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.03128 ( -0.0898922 0.0917248 )
Norm@50keV : 3.44510E-02 ( -0.00187769 0.0018622 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 55.81 using 59 bins.
Reduced chi-squared = 0.979123
# Null hypothesis probability of 5.20e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 28.16 sec: 3.97370 ( -0.2258 0.22679 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.03777e-05 ( -5.24426e-07 5.24666e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -7.040 sec. to 21.120 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.02503 ( -0.106016 0.367008 )
Epeak [keV] : 9999.99 ( -9999.99 -9999.99 )
Norm@50keV : 3.46515E-02 ( -0.00187888 0.00172177 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 55.81 using 59 bins.
Reduced chi-squared = 0.996607
# Null hypothesis probability of 4.82e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 28.16 sec: 3.97132 ( -0.23369 0.2282 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.03818e-05 ( -5.19856e-07 5.12078e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.180 sec. to 1.180 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.919778 ( -0.210331 0.219477 )
Norm@50keV : 8.63562E-02 ( -0.01208 0.0119194 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 66.97 using 59 bins.
Reduced chi-squared = 1.17491
# Null hypothesis probability of 1.72e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.102950 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 9.619e-07 ( -1.2818e-07 1.28284e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.180 sec. to 1.180 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.220065 ( -0.9826 1.25958 )
Epeak [keV] : 124.516 ( -34.5802 320.669 )
Norm@50keV : 0.244962 ( -0.143571 0.460534 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 62.97 using 59 bins.
Reduced chi-squared = 1.12446
# Null hypothesis probability of 2.43e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 2.35713E-02 ( -0.0235713 -0.0235713 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.54113e-07 ( -1.33591e-07 1.32238e-07 ) ergs/cm2
Time-resolved spectra
