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 -1.448 sec. to 271.204 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.25351 ( -0.0597708 0.0599395 )
Norm@50keV : 2.96169E-03 ( -9.0685e-05 9.06772e-05 )
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#Fit statistic : Chi-Squared = 52.47 using 59 PHA bins.
# Reduced chi-squared = 0.9204 for 57 degrees of freedom
# Null hypothesis probability = 6.456573e-01
Photon flux (15-150 keV) in 272.7 sec: 0.350492 ( -0.011384 0.011419 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.07634e-06 ( -2.72735e-07 2.73829e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.448 sec. to 271.204 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.15908 ( -0.120567 0.238084 )
Epeak [keV] : 495.380 ( -495.441 -495.441 )
Norm@50keV : 3.26734E-03 ( -0.000491682 0.000888183 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.97 using 59 PHA bins.
# Reduced chi-squared = 0.9280 for 56 degrees of freedom
# Null hypothesis probability = 6.281245e-01
Photon flux (15-150 keV) in 272.7 sec: 0.348155 ( -0.012633 0.012598 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.0191e-06 ( -3.06599e-07 3.0381e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 7.264 sec. to 8.264 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.863463 ( -0.0741684 0.0746961 )
Norm@50keV : 6.67121E-02 ( -0.00271614 0.00271093 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.15 using 59 PHA bins.
# Reduced chi-squared = 1.178 for 57 degrees of freedom
# Null hypothesis probability = 1.682389e-01
Photon flux (15-150 keV) in 1 sec: 7.65685 ( -0.3106 0.3107 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.59626e-07 ( -3.51233e-08 3.52694e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 7.264 sec. to 8.264 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.687076 ( -0.223742 0.304523 )
Epeak [keV] : 437.420 ( -437.42 -437.42 )
Norm@50keV : 7.95734E-02 ( -0.0150474 0.0272596 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.06 using 59 PHA bins.
# Reduced chi-squared = 1.180 for 56 degrees of freedom
# Null hypothesis probability = 1.682605e-01
Photon flux (15-150 keV) in 1 sec: 7.59784 ( -0.32508 0.32453 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.52749e-07 ( -3.72978e-08 3.70926e-08 ) ergs/cm2
Time-resolved spectra
