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 -48.140 sec. to 705.776 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.66075 ( -0.0570713 0.0569761 )
Norm@50keV : 2.80031E-03 ( -8.50317e-05 8.50102e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.53 using 59 PHA bins.
# Reduced chi-squared = 0.7813 for 57 degrees of freedom
# Null hypothesis probability = 8.853150e-01
Photon flux (15-150 keV) in 753.9 sec: 0.366972 ( -0.012573 0.012624 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.96166e-05 ( -6.13997e-07 6.15135e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -48.140 sec. to 705.776 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.42786 ( -0.223617 0.235622 )
Epeak [keV] : 131.726 ( -40.6963 868.272 )
Norm@50keV : 3.60029E-03 ( -0.000754083 0.00101209 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 41.37 using 59 PHA bins.
# Reduced chi-squared = 0.7388 for 56 degrees of freedom
# Null hypothesis probability = 9.279019e-01
Photon flux (15-150 keV) in 753.9 sec: 0.360475 ( -0.013898 0.013966 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.93078e-05 ( -6.83369e-07 6.80831e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 93.584 sec. to 94.584 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.58792 ( -0.221935 0.217534 )
Norm@50keV : 2.19124E-02 ( -0.00282874 0.00280999 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.15 using 59 PHA bins.
# Reduced chi-squared = 1.055 for 57 degrees of freedom
# Null hypothesis probability = 3.623411e-01
Photon flux (15-150 keV) in 1 sec: 2.80550 ( -0.36683 0.36837 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.05263e-07 ( -2.80931e-08 2.82709e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 93.584 sec. to 94.584 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.35384 ( -0.444519 0.91339 )
Epeak [keV] : 146.958 ( -146.964 -146.964 )
Norm@50keV : 2.84429E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.90 using 59 PHA bins.
# Reduced chi-squared = 1.070 for 56 degrees of freedom
# Null hypothesis probability = 3.361131e-01
Photon flux (15-150 keV) in 1 sec: 2.77637 ( -0.38147 0.38 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.03161e-07 ( -2.91447e-08 2.91234e-08 ) ergs/cm2
Time-resolved spectra
