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 0.000 sec. to 33.400 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.3406 ( -0.0445202 0.0446184 )
Norm@50keV : 1.17058E-02 ( -0.000275463 0.000275424 )
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#Fit statistic : Chi-Squared = 55.23 using 59 PHA bins.
# Reduced chi-squared = 0.9689 for 57 degrees of freedom
# Null hypothesis probability = 5.417842e-01
Photon flux (15-150 keV) in 33.4 sec: 1.40754 ( -0.03629 0.03637 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.82717e-06 ( -9.53029e-08 9.53593e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 33.400 sec.
Spectral model in the cutoff power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.08897 ( -0.175113 0.182344 )
Epeak [keV] : 204.346 ( -62.1432 305.593 )
Norm@50keV : 1.51529E-02 ( -0.00243063 0.00301895 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.12 using 59 PHA bins.
# Reduced chi-squared = 0.8771 for 56 degrees of freedom
# Null hypothesis probability = 7.309116e-01
Photon flux (15-150 keV) in 33.4 sec: 1.38227 ( -0.03989 0.04001 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.76562e-06 ( -1.04812e-07 1.04433e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 2.784 sec. to 3.784 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.12141 ( -0.0516546 0.0517999 )
Norm@50keV : 7.29850E-02 ( -0.00216017 0.00215957 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.25 using 59 PHA bins.
# Reduced chi-squared = 0.8114 for 57 degrees of freedom
# Null hypothesis probability = 8.449151e-01
Photon flux (15-150 keV) in 1 sec: 0.498174 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 7.58019e-07 ( -2.44516e-08 2.45092e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.784 sec. to 3.784 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.699286 ( -0.214115 0.224616 )
Epeak [keV] : 176.843 ( -41.9068 117.172 )
Norm@50keV : 0.112536 ( -0.0216746 0.0282039 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 34.45 using 59 PHA bins.
# Reduced chi-squared = 0.6152 for 56 degrees of freedom
# Null hypothesis probability = 9.896347e-01
Photon flux (15-150 keV) in 1 sec: 8.32476 ( -0.27043 0.27071 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.83493e-07 ( -2.50839e-08 1.35904e-08 ) ergs/cm2
Time-resolved spectra
