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 -21.488 sec. to 38.956 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.41327 ( -0.0318548 0.0319564 )
Norm@50keV : 3.08494E-02 ( -0.000510722 0.000510004 )
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#Fit statistic : Chi-Squared = 45.57 using 59 PHA bins.
# Reduced chi-squared = 0.7995 for 57 degrees of freedom
# Null hypothesis probability = 8.616884e-01
Photon flux (15-150 keV) in 60.44 sec: 3.76843 ( -0.07377 0.07405 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.79703e-05 ( -2.92615e-07 2.93256e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -21.488 sec. to 38.956 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.40969 ( -0.0141818 0.126688 )
Epeak [keV] : 9999.09 ( -9999.1 -9999.1 )
Norm@50keV : 3.09563E-02 ( -0.000504379 0.00355817 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.58 using 59 PHA bins.
# Reduced chi-squared = 0.8139 for 56 degrees of freedom
# Null hypothesis probability = 8.387393e-01
Photon flux (15-150 keV) in 60.44 sec: 2.53015 ( -0.10746 0.06527 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.15575e-06 ( -4.34388e-07 3.36175e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.132 sec. to 2.132 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.19458 ( -0.0582187 0.0582622 )
Norm@50keV : 0.181311 ( -0.00578164 0.00578162 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.41 using 59 PHA bins.
# Reduced chi-squared = 1.060 for 57 degrees of freedom
# Null hypothesis probability = 3.535866e-01
Photon flux (15-150 keV) in 1 sec: 1.17631 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.84251e-06 ( -6.62358e-08 6.642e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.132 sec. to 2.132 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.03275 ( -0.184718 0.224545 )
Epeak [keV] : 330.700 ( -330.7 -330.7 )
Norm@50keV : 0.215302 ( -0.0371914 0.0559716 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.75 using 59 PHA bins.
# Reduced chi-squared = 1.049 for 56 degrees of freedom
# Null hypothesis probability = 3.750459e-01
Photon flux (15-150 keV) in 1 sec: 21.0901 ( -0.7338 0.7342 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.82402e-06 ( -7.11085e-08 7.08525e-08 ) ergs/cm2
Time-resolved spectra
