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 -5.192 sec. to 36.464 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.52721 ( -0.0605777 0.0605786 )
Norm@50keV : 1.11885E-02 ( -0.000362769 0.000362769 )
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#Fit statistic : Chi-Squared = 41.10 using 59 PHA bins.
# Reduced chi-squared = 0.7210 for 57 degrees of freedom
# Null hypothesis probability = 9.443102e-01
Photon flux (15-150 keV) in 41.66 sec: 1.40727 ( -0.05143 0.05172 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.40342e-06 ( -1.48325e-07 1.48339e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -5.192 sec. to 36.464 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.52454 ( -0.149759 0.205009 )
Epeak [keV] : 9997.61 ( -9997.48 -9997.48 )
Norm@50keV : 1.12204E-02 ( -0.000363819 0.00311636 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.09 using 59 PHA bins.
# Reduced chi-squared = 0.7338 for 56 degrees of freedom
# Null hypothesis probability = 9.322691e-01
Photon flux (15-150 keV) in 41.66 sec: 1.40593 ( -0.05671 0.05352 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.40025e-06 ( -1.5983e-07 1.52448e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 21.576 sec. to 22.576 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.37605 ( -0.198219 0.200676 )
Norm@50keV : 2.05433E-02 ( -0.00229029 0.00229018 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.17 using 59 PHA bins.
# Reduced chi-squared = 1.073 for 57 degrees of freedom
# Null hypothesis probability = 3.287866e-01
Photon flux (15-150 keV) in 1 sec: 2.48857 ( -0.29527 0.29665 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.99522e-07 ( -2.38591e-08 2.39587e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 21.576 sec. to 22.576 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.47018 ( -0.195518 0.29097 )
Epeak [keV] : 157.646 ( -9999.36 -9999.36 )
Norm@50keV : 4.63597E-03 ( -0.00213693 0.00510721 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.19 using 59 PHA bins.
# Reduced chi-squared = 1.075 for 56 degrees of freedom
# Null hypothesis probability = 3.266914e-01
Photon flux (15-150 keV) in 1 sec: 0.914288 ( -0.411705 0.726792 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.00928e-07 ( -2.54228e-08 2.26299e-08 ) ergs/cm2
Time-resolved spectra
