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 -25.544 sec. to 31.800 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.78847 ( -0.155141 0.151398 )
Norm@50keV : 2.79468E-03 ( -0.000258366 0.00025392 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.77 using 59 PHA bins.
# Reduced chi-squared = 0.9258 for 57 degrees of freedom
# Null hypothesis probability = 6.343175e-01
Photon flux (15-150 keV) in 57.34 sec: 0.383412 ( -0.031119 0.03116 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.4761e-06 ( -1.38746e-07 1.4059e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -25.544 sec. to 31.800 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.79483 ( -0.150979 0.347534 )
Epeak [keV] : 9999.36 ( -9999.35 -9999.36 )
Norm@50keV : 2.78477E-03 ( -0.00159807 0.0014235 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.79 using 59 PHA bins.
# Reduced chi-squared = 0.9426 for 56 degrees of freedom
# Null hypothesis probability = 5.972676e-01
Photon flux (15-150 keV) in 57.34 sec: 0.383829 ( -0.03174 0.03102 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.4861e-06 ( -1.83268e-07 1.61373e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.388 sec. to 0.612 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.60393 ( -0.34133 0.328515 )
Norm@50keV : 8.64114E-03 ( -0.00195108 0.00191694 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.99 using 59 PHA bins.
# Reduced chi-squared = 0.8419 for 57 degrees of freedom
# Null hypothesis probability = 7.967163e-01
Photon flux (15-150 keV) in 1 sec: 1.11183 ( -0.234474 0.23466 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.07811e-08 ( -1.91301e-08 1.95094e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.388 sec. to 0.612 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.148768 ( -1.56902 2.99748 )
Epeak [keV] : 56.1605 ( -15.9804 -56.1457 )
Norm@50keV : 5.60556E-02 ( -0.0561526 3.034 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.69 using 59 PHA bins.
# Reduced chi-squared = 0.8158 for 56 degrees of freedom
# Null hypothesis probability = 8.358892e-01
Photon flux (15-150 keV) in 1 sec: 1.07430 ( -0.242485 0.2406 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.17811e-08 ( -2.05752e-08 2.2293e-08 ) ergs/cm2
Time-resolved spectra
