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 -46.080 sec. to 85.592 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.64498 ( -0.0591576 0.058949 )
Norm@50keV : 4.54023E-03 ( -0.000145562 0.000145452 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.11 using 59 PHA bins.
# Reduced chi-squared = 0.9318 for 57 degrees of freedom
# Null hypothesis probability = 6.216123e-01
Photon flux (15-150 keV) in 131.7 sec: 0.591886 ( -0.020547 0.020613 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.56475e-06 ( -1.86313e-07 1.86682e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -46.080 sec. to 85.592 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.28409 ( -0.241253 0.25531 )
Epeak [keV] : 103.830 ( -22.9728 97.2524 )
Norm@50keV : 6.76014E-03 ( -0.00154374 0.00214021 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.44 using 59 PHA bins.
# Reduced chi-squared = 0.8293 for 56 degrees of freedom
# Null hypothesis probability = 8.149764e-01
Photon flux (15-150 keV) in 131.7 sec: 0.577095 ( -0.022554 0.022671 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.42246e-06 ( -2.09842e-07 2.09065e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 15.476 sec. to 16.476 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.42653 ( -0.129543 0.129823 )
Norm@50keV : 2.52837E-02 ( -0.00204036 0.00203877 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.78 using 59 PHA bins.
# Reduced chi-squared = 1.119 for 57 degrees of freedom
# Null hypothesis probability = 2.502787e-01
Photon flux (15-150 keV) in 1 sec: 3.09820 ( -0.25761 0.25806 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.43052e-07 ( -2.10535e-08 2.11706e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 15.476 sec. to 16.476 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.433435 ( -0.600478 0.699191 )
Epeak [keV] : 80.5772 ( -15.0822 45.9554 )
Norm@50keV : 7.88589E-02 ( -0.0385476 0.0920968 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.15 using 59 PHA bins.
# Reduced chi-squared = 0.9848 for 56 degrees of freedom
# Null hypothesis probability = 5.070151e-01
Photon flux (15-150 keV) in 1 sec: 2.99520 ( -0.26664 0.26636 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.29774e-07 ( -2.26502e-08 2.28008e-08 ) ergs/cm2
Time-resolved spectra
