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 -48.956 sec. to 25.444 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.67201 ( -0.126973 0.125111 )
Norm@50keV : 2.45783E-03 ( -0.000195506 0.000194676 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.33 using 59 PHA bins.
# Reduced chi-squared = 1.269 for 57 degrees of freedom
# Null hypothesis probability = 8.296464e-02
Photon flux (15-150 keV) in 74.4 sec: 0.323312 ( -0.025596 0.025652 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.69739e-06 ( -1.40591e-07 1.41486e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -48.956 sec. to 25.444 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.424012 ( -0.587303 0.673985 )
Epeak [keV] : 61.9489 ( -8.23547 15.0161 )
Norm@50keV : 1.06466E-02 ( -0.00522032 0.0125386 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.32 using 59 PHA bins.
# Reduced chi-squared = 1.024 for 56 degrees of freedom
# Null hypothesis probability = 4.260018e-01
Photon flux (15-150 keV) in 74.4 sec: 0.307221 ( -0.026502 0.026592 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.57693e-06 ( -1.48717e-07 1.51106e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 3.052 sec. to 4.052 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.67716 ( -0.372798 0.357896 )
Norm@50keV : 8.18457E-03 ( -0.00180886 0.0017647 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.46 using 59 PHA bins.
# Reduced chi-squared = 1.096 for 57 degrees of freedom
# Null hypothesis probability = 2.885874e-01
Photon flux (15-150 keV) in 1 sec: 1.07852 ( -0.226399 0.22696 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.59347e-08 ( -1.7333e-08 1.7552e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 3.052 sec. to 4.052 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.65518 ( )
Epeak [keV] : 642.153 ( )
Norm@50keV : 8.41252E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.47 using 59 PHA bins.
# Reduced chi-squared = 1.116 for 56 degrees of freedom
# Null hypothesis probability = 2.572572e-01
Photon flux (15-150 keV) in 1 sec: 1.08014 ( -0.230708 0.22778 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.61185e-08 ( -1.84086e-08 1.75492e-08 ) ergs/cm2
Time-resolved spectra
