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 -0.004 sec. to 41.688 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.8598 ( -0.0402425 0.0401202 )
Norm@50keV : 1.59180E-02 ( -0.000328262 0.000328061 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.40 using 59 PHA bins.
# Reduced chi-squared = 1.095 for 57 degrees of freedom
# Null hypothesis probability = 2.903996e-01
Photon flux (15-150 keV) in 41.69 sec: 2.24654 ( -0.05379 0.05403 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.10212e-06 ( -1.26106e-07 1.26354e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.004 sec. to 41.688 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.31845 ( -0.179162 0.186476 )
Epeak [keV] : 64.9227 ( -5.39422 8.4619 )
Norm@50keV : 2.88377E-02 ( -0.0050475 0.00641864 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 33.85 using 59 PHA bins.
# Reduced chi-squared = 0.6044 for 56 degrees of freedom
# Null hypothesis probability = 9.916379e-01
Photon flux (15-150 keV) in 41.69 sec: 2.13708 ( -0.06255 0.06304 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.83043e-06 ( -1.52345e-07 1.52197e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 21.684 sec. to 22.684 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.28674 ( -0.0479102 0.0479048 )
Norm@50keV : 0.108700 ( -0.00306498 0.00306489 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 81.04 using 59 PHA bins.
# Reduced chi-squared = 1.422 for 57 degrees of freedom
# Null hypothesis probability = 1.989032e-02
Photon flux (15-150 keV) in 1 sec: 0.355356 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.0778e-06 ( -3.26226e-08 3.26525e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 21.684 sec. to 22.684 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.495255 ( -0.219276 0.229842 )
Epeak [keV] : 107.708 ( -12.3732 20.0233 )
Norm@50keV : 0.246695 ( -0.04887 0.0640945 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 38.69 using 59 PHA bins.
# Reduced chi-squared = 0.6909 for 56 degrees of freedom
# Null hypothesis probability = 9.622937e-01
Photon flux (15-150 keV) in 1 sec: 12.4615 ( -0.4004 0.4018 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.04311e-06 ( -3.46701e-08 3.45953e-08 ) ergs/cm2
Time-resolved spectra
