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 -24.276 sec. to 170.716 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.41628 ( -0.0821192 0.0820848 )
Norm@50keV : 1.64182E-03 ( -7.63916e-05 7.63351e-05 )
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#Fit statistic : Chi-Squared = 71.15 using 59 PHA bins.
# Reduced chi-squared = 1.248 for 57 degrees of freedom
# Null hypothesis probability = 9.850769e-02
Photon flux (15-150 keV) in 195 sec: 0.200698 ( -0.009613 0.009628 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.08379e-06 ( -1.57517e-07 1.58298e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -24.276 sec. to 170.716 sec.
Spectral model in the cutoff power-law:
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Parameters : value lower 90% higher 90%
Photon index: -0.785261 ( -0.358078 0.391159 )
Epeak [keV] : 98.4923 ( -19.9707 60.9847 )
Norm@50keV : 3.34808E-03 ( -0.00109232 0.00181134 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.55 using 59 PHA bins.
# Reduced chi-squared = 1.099 for 56 degrees of freedom
# Null hypothesis probability = 2.840517e-01
Photon flux (15-150 keV) in 195 sec: 0.193890 ( -0.010318 0.010318 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.93186e-06 ( -1.80205e-07 1.801e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 5.044 sec. to 6.044 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.45085 ( -0.189135 0.185929 )
Norm@50keV : 1.07697E-02 ( -0.00129208 0.00128259 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.55 using 59 PHA bins.
# Reduced chi-squared = 1.080 for 57 degrees of freedom
# Null hypothesis probability = 3.164019e-01
Photon flux (15-150 keV) in 1 sec: 1.32753 ( -0.15264 0.15268 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.03058e-07 ( -1.36472e-08 1.383e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 5.044 sec. to 6.044 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.224184 ( -0.916999 1.16901 )
Epeak [keV] : 67.8616 ( -14.682 63.9305 )
Norm@50keV : 4.83338E-02 ( -0.0483379 0.152495 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.04 using 59 PHA bins.
# Reduced chi-squared = 1.001 for 56 degrees of freedom
# Null hypothesis probability = 4.733908e-01
Photon flux (15-150 keV) in 1 sec: 1.27404 ( -0.15859 0.15825 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.2933e-08 ( -1.50218e-08 1.57221e-08 ) ergs/cm2
Time-resolved spectra
