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 -10.088 sec. to 105.384 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.9593 ( -0.114722 0.111876 )
Norm@50keV : 1.91061E-03 ( -0.000128967 0.000127281 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.11 using 59 PHA bins.
# Reduced chi-squared = 0.8089 for 57 degrees of freedom
# Null hypothesis probability = 8.485187e-01
Photon flux (15-150 keV) in 115.5 sec: 0.281378 ( -0.016301 0.016341 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.03176e-06 ( -1.31287e-07 1.32611e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -10.088 sec. to 105.384 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.82636 ( -0.401953 0.452559 )
Epeak [keV] : 58.7929 ( -48.3129 -58.7929 )
Norm@50keV : 2.25632E-03 ( -0.00085039 0.00167755 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.81 using 59 PHA bins.
# Reduced chi-squared = 0.8181 for 56 degrees of freedom
# Null hypothesis probability = 8.324469e-01
Photon flux (15-150 keV) in 115.5 sec: 0.279148 ( -0.017687 0.017664 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.00393e-06 ( -1.56648e-07 1.31537e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.224 sec. to 1.224 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.94974 ( -0.305583 0.282846 )
Norm@50keV : 9.56896E-03 ( -0.00185643 0.00178415 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.66 using 59 PHA bins.
# Reduced chi-squared = 0.9764 for 57 degrees of freedom
# Null hypothesis probability = 5.256324e-01
Photon flux (15-150 keV) in 1 sec: 1.40327 ( -0.21767 0.2178 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.80745e-08 ( -1.6065e-08 1.64192e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.224 sec. to 1.224 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.95996 ( -0.300406 0.29148 )
Epeak [keV] : 9999.36 ( )
Norm@50keV : 9.51148E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.66 using 59 PHA bins.
# Reduced chi-squared = 0.9939 for 56 degrees of freedom
# Null hypothesis probability = 4.877689e-01
Photon flux (15-150 keV) in 1 sec: 1.40443 ( -0.11116 0.21744 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.82206e-08 ( -1.06834e-08 1.30142e-08 ) ergs/cm2
Time-resolved spectra
