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 -0.212 sec. to 26.720 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.82394 ( -0.0625572 0.0621259 )
Norm@50keV : 8.91379E-03 ( -0.000286178 0.000285331 )
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#Fit statistic : Chi-Squared = 46.18 using 59 PHA bins.
# Reduced chi-squared = 0.8102 for 57 degrees of freedom
# Null hypothesis probability = 8.466841e-01
Photon flux (15-150 keV) in 26.93 sec: 1.23995 ( -0.04174 0.04192 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.20865e-06 ( -7.18355e-08 7.20426e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.212 sec. to 26.720 sec.
Spectral model in the cutoff power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.59751 ( -0.238986 0.254569 )
Epeak [keV] : 88.0198 ( -23.3398 -88.0198 )
Norm@50keV : 1.15444E-02 ( -0.00268708 0.00379569 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.60 using 59 PHA bins.
# Reduced chi-squared = 0.7785 for 56 degrees of freedom
# Null hypothesis probability = 8.863868e-01
Photon flux (15-150 keV) in 26.93 sec: 1.21635 ( -0.04813 0.04835 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.004 sec. to 2.004 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.43377 ( -0.0965682 0.0961552 )
Norm@50keV : 3.06030E-02 ( -0.00166569 0.00165991 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.11 using 59 PHA bins.
# Reduced chi-squared = 0.9141 for 57 degrees of freedom
# Null hypothesis probability = 6.588123e-01
Photon flux (15-150 keV) in 1 sec: 3.75653 ( -0.20513 0.20537 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.93778e-07 ( -1.7752e-08 1.78741e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.004 sec. to 2.004 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.08832 ( -0.372574 0.405773 )
Epeak [keV] : 134.236 ( -47.2423 -134.236 )
Norm@50keV : 4.53999E-02 ( -0.0151728 0.0259342 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.58 using 59 PHA bins.
# Reduced chi-squared = 0.8854 for 56 degrees of freedom
# Null hypothesis probability = 7.149164e-01
Photon flux (15-150 keV) in 1 sec: 3.68834 ( -0.21756 0.21747 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.85568e-07 ( -1.99791e-08 1.99171e-08 ) ergs/cm2
Time-resolved spectra
