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 -34.060 sec. to 70.236 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.77451 ( -0.0852805 0.0845965 )
Norm@50keV : 4.44390E-03 ( -0.000212592 0.000212049 )
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#Fit statistic : Chi-Squared = 71.10 using 59 PHA bins.
# Reduced chi-squared = 1.247 for 57 degrees of freedom
# Null hypothesis probability = 9.913289e-02
Photon flux (15-150 keV) in 104.3 sec: 0.606445 ( -0.030751 0.030867 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.27213e-06 ( -2.08403e-07 2.08968e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -34.060 sec. to 70.236 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.48251 ( -0.321561 0.3546 )
Epeak [keV] : 89.7934 ( -25.0477 -89.7936 )
Norm@50keV : 6.20471E-03 ( -0.00184077 0.00301905 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.82 using 59 PHA bins.
# Reduced chi-squared = 1.229 for 56 degrees of freedom
# Null hypothesis probability = 1.166938e-01
Photon flux (15-150 keV) in 104.3 sec: 0.595489 ( -0.03296 0.033085 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.18739e-06 ( -2.20923e-07 2.29473e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.980 sec. to 2.980 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.53799 ( -0.171868 0.170255 )
Norm@50keV : 2.98442E-02 ( -0.0028582 0.0028521 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.63 using 59 PHA bins.
# Reduced chi-squared = 0.8006 for 57 degrees of freedom
# Null hypothesis probability = 8.602464e-01
Photon flux (15-150 keV) in 1 sec: 3.76519 ( -0.38026 0.38155 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.81482e-07 ( -2.86978e-08 2.87953e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.980 sec. to 2.980 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.54057 ( -0.168397 0.175709 )
Epeak [keV] : 9999.35 ( -9999.36 -9999.36 )
Norm@50keV : 2.99126E-02 ( -0.0299156 0.015408 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.65 using 59 PHA bins.
# Reduced chi-squared = 0.8151 for 56 degrees of freedom
# Null hypothesis probability = 8.369547e-01
Photon flux (15-150 keV) in 1 sec: 3.80321 ( -0.41864 0.34321 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.83936e-07 ( -3.11925e-08 2.62841e-08 ) ergs/cm2
Time-resolved spectra
