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 -13.280 sec. to 233.420 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.57131 ( -0.061027 0.0608669 )
Norm@50keV : 2.31872E-03 ( -7.17833e-05 7.16844e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.88 using 59 PHA bins.
# Reduced chi-squared = 0.7172 for 57 degrees of freedom
# Null hypothesis probability = 9.471233e-01
Photon flux (15-150 keV) in 246.7 sec: 0.295389 ( -0.00982 0.009866 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.37007e-06 ( -1.78014e-07 1.78479e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -13.280 sec. to 233.420 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.57125 ( -0.0600781 0.112921 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 2.31957E-03 ( -7.18398e-05 0.000467427 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.91 using 59 PHA bins.
# Reduced chi-squared = 0.7305 for 56 degrees of freedom
# Null hypothesis probability = 9.350110e-01
Photon flux (15-150 keV) in 246.7 sec: 0.296809 ( -0.012541 0.009393 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.36896e-06 ( -1.63976e-07 1.78439e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 21.256 sec. to 22.256 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.13916 ( -0.107594 0.108224 )
Norm@50keV : 2.41255E-02 ( -0.00138245 0.00138237 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.63 using 59 PHA bins.
# Reduced chi-squared = 0.9760 for 57 degrees of freedom
# Null hypothesis probability = 5.264739e-01
Photon flux (15-150 keV) in 1 sec: 2.80998 ( -0.16529 0.16561 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.49201e-07 ( -1.62364e-08 1.63268e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 21.256 sec. to 22.256 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.14038 ( -0.102924 0.114666 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 2.42485E-02 ( -0.001389 0.00476322 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.70 using 59 PHA bins.
# Reduced chi-squared = 0.9947 for 56 degrees of freedom
# Null hypothesis probability = 4.861066e-01
Photon flux (15-150 keV) in 1 sec: 2.82860 ( -0.18466 0.14623 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.49109e-07 ( -1.62463e-08 1.6321e-08 ) ergs/cm2
Time-resolved spectra
