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 -0.072 sec. to 0.504 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.12372 ( -0.496848 0.423852 )
Norm@50keV : 5.54291E-03 ( -0.00189762 0.00183566 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.64 using 59 PHA bins.
# Reduced chi-squared = 0.8182 for 57 degrees of freedom
# Null hypothesis probability = 8.347757e-01
Photon flux (15-150 keV) in 0.576 sec: 0.882470 ( -0.207503 0.20761 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.97415e-08 ( -8.72726e-09 9.34733e-09 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.072 sec. to 0.504 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.888613 ( -1.22155 3.33423 )
Epeak [keV] : 33.6892 ( )
Norm@50keV : 3.22977E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.47 using 59 PHA bins.
# Reduced chi-squared = 0.8120 for 56 degrees of freedom
# Null hypothesis probability = 8.415607e-01
Photon flux (15-150 keV) in 0.576 sec: 0.857807 ( -0.207059 0.209533 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.63883e-08 ( -8.17068e-09 1.04943e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.284 sec. to 0.716 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.84172 ( -0.561888 0.499921 )
Norm@50keV : 3.61406E-03 ( -0.00135356 0.00130995 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 74.66 using 59 PHA bins.
# Reduced chi-squared = 1.310 for 57 degrees of freedom
# Null hypothesis probability = 5.821682e-02
Photon flux (15-150 keV) in 1 sec: 0.506325 ( -0.152808 0.152818 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.32491e-08 ( -1.18941e-08 1.27999e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.284 sec. to 0.716 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.0933134 ( -2.27462 5.28246 )
Epeak [keV] : 42.2734 ( )
Norm@50keV : 5.24666E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.64 using 59 PHA bins.
# Reduced chi-squared = 1.297 for 56 degrees of freedom
# Null hypothesis probability = 6.671734e-02
Photon flux (15-150 keV) in 1 sec: 0.480170 ( -0.15009 0.153001 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.74069e-08 ( -1.00705e-08 1.37014e-08 ) ergs/cm2
Time-resolved spectra
