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 -8.952 sec. to 10.888 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.13667 ( -0.307117 0.277724 )
Norm@50keV : 2.10928E-03 ( -0.000458831 0.000447693 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.78 using 59 PHA bins.
# Reduced chi-squared = 0.9786 for 57 degrees of freedom
# Null hypothesis probability = 5.209822e-01
Photon flux (15-150 keV) in 19.84 sec: 0.338010 ( -0.053386 0.053386 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.90384e-07 ( -7.44022e-08 7.70088e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -8.952 sec. to 10.888 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.24279 ( -1.76952 2.54741 )
Epeak [keV] : 35.6306 ( -10.957 8.38036 )
Norm@50keV : 5.92231E-02 ( -0.0636059 2.26374 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.82 using 59 PHA bins.
# Reduced chi-squared = 0.8896 for 56 degrees of freedom
# Null hypothesis probability = 7.066803e-01
Photon flux (15-150 keV) in 19.84 sec: 0.319825 ( -0.053657 0.054116 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.30431e-07 ( -6.33942e-08 7.65382e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 2.412 sec. to 3.412 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.24224 ( -0.6276 0.509829 )
Norm@50keV : 4.88249E-03 ( -0.00208581 0.00203315 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.31 using 59 PHA bins.
# Reduced chi-squared = 1.128 for 57 degrees of freedom
# Null hypothesis probability = 2.360303e-01
Photon flux (15-150 keV) in 1 sec: 0.826782 ( -0.237157 0.237298 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.62083e-08 ( -1.6151e-08 1.74654e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.412 sec. to 3.412 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.79571 ( -3.27521 7.70596 )
Epeak [keV] : 30.7047 ( -23.9527 -30.4744 )
Norm@50keV : 2.27203 ( -2.17221 55817.8 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.26 using 59 PHA bins.
# Reduced chi-squared = 1.112 for 56 degrees of freedom
# Null hypothesis probability = 2.633753e-01
Photon flux (15-150 keV) in 1 sec: 0.782652 ( -0.227606 0.231018 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.63814e-08 ( -1.124e-08 1.88721e-08 ) ergs/cm2
Time-resolved spectra
