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 -1.564 sec. to 26.588 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.63491 ( -0.0741497 0.0737026 )
Norm@50keV : 5.72016E-03 ( -0.00022302 0.000222264 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.37 using 59 PHA bins.
# Reduced chi-squared = 0.6557 for 57 degrees of freedom
# Null hypothesis probability = 9.793692e-01
Photon flux (15-150 keV) in 28.15 sec: 0.743267 ( -0.030291 0.030423 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.50013e-06 ( -6.19635e-08 6.21867e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.564 sec. to 26.588 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.63301 ( -0.109799 0.250168 )
Epeak [keV] : 9996.98 ( -9996.9 -9996.91 )
Norm@50keV : 5.73271E-03 ( -0.000218944 0.00207839 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.37 using 59 PHA bins.
# Reduced chi-squared = 0.6674 for 56 degrees of freedom
# Null hypothesis probability = 9.738053e-01
Photon flux (15-150 keV) in 28.15 sec: 0.743099 ( -0.033537 0.030201 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.49989e-06 ( -7.02728e-08 6.16736e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.220 sec. to 2.220 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.33251 ( -0.124822 0.125005 )
Norm@50keV : 1.61510E-02 ( -0.0012591 0.00125779 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 69.17 using 59 PHA bins.
# Reduced chi-squared = 1.214 for 57 degrees of freedom
# Null hypothesis probability = 1.294174e-01
Photon flux (15-150 keV) in 1 sec: 1.93891 ( -0.15239 0.15253 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.58391e-07 ( -1.36305e-08 1.37364e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.220 sec. to 2.220 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.256594 ( -0.553008 0.635662 )
Epeak [keV] : 81.9978 ( -14.4884 34.696 )
Norm@50keV : 5.56859E-02 ( -0.0256913 0.0573806 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.77 using 59 PHA bins.
# Reduced chi-squared = 1.014 for 56 degrees of freedom
# Null hypothesis probability = 4.461748e-01
Photon flux (15-150 keV) in 1 sec: 1.86555 ( -0.15706 0.15708 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.47258e-07 ( -1.47293e-08 1.49081e-08 ) ergs/cm2
Time-resolved spectra
