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 -1.624 sec. to 24.100 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.71683 ( -0.162762 0.159191 )
Norm@50keV : 4.46748E-03 ( -0.000457013 0.000451684 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.87 using 59 PHA bins.
# Reduced chi-squared = 1.015 for 57 degrees of freedom
# Null hypothesis probability = 4.428182e-01
Photon flux (15-150 keV) in 25.72 sec: 0.596889 ( -0.056212 0.056257 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.06268e-06 ( -1.12813e-07 1.14065e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.624 sec. to 24.100 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.06954 ( -0.700791 0.903193 )
Epeak [keV] : 63.4907 ( -16.5215 -63.4759 )
Norm@50keV : 1.02609E-02 ( -0.00596507 0.0228319 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.55 using 59 PHA bins.
# Reduced chi-squared = 0.9919 for 56 degrees of freedom
# Null hypothesis probability = 4.919073e-01
Photon flux (15-150 keV) in 25.72 sec: 0.583106 ( -0.058766 0.058499 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.96578e-07 ( -1.35919e-07 1.36034e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.300 sec. to 0.700 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.62838 ( -0.182805 0.180427 )
Norm@50keV : 2.07442E-02 ( -0.00257668 0.00256138 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 75.46 using 59 PHA bins.
# Reduced chi-squared = 1.324 for 57 degrees of freedom
# Null hypothesis probability = 5.136634e-02
Photon flux (15-150 keV) in 1 sec: 2.68977 ( -0.3273 0.32769 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.93397e-07 ( -2.51373e-08 2.52986e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.300 sec. to 0.700 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.243811 ( -1.13386 1.56119 )
Epeak [keV] : 53.3427 ( -8.21983 18.3958 )
Norm@50keV : 0.226115 ( -0.227938 1.44248 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.14 using 59 PHA bins.
# Reduced chi-squared = 1.181 for 56 degrees of freedom
# Null hypothesis probability = 1.666024e-01
Photon flux (15-150 keV) in 1 sec: 2.60141 ( -0.33826 0.3359 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.71348e-07 ( -2.68207e-08 2.83943e-08 ) ergs/cm2
Time-resolved spectra
