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 -0.068 sec. to 1.076 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.890379 ( -0.263454 0.280981 )
Norm@50keV : 7.97894E-03 ( -0.00128425 0.00126532 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.34 using 59 PHA bins.
# Reduced chi-squared = 1.023 for 57 degrees of freedom
# Null hypothesis probability = 4.260419e-01
Photon flux (15-150 keV) in 1.144 sec: 0.915738 ( -0.14592 0.146742 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.02836e-07 ( -1.65432e-08 1.66302e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.068 sec. to 1.076 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.321707 ( -0.693954 1.51725 )
Epeak [keV] : 174.632 ( -174.617 -174.617 )
Norm@50keV : 1.40186E-02 ( -0.00704798 0.0435379 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.63 using 59 PHA bins.
# Reduced chi-squared = 1.029 for 56 degrees of freedom
# Null hypothesis probability = 4.147648e-01
Photon flux (15-150 keV) in 1.144 sec: 0.895531 ( -0.15278 0.152369 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.00368e-07 ( -1.80442e-08 1.75189e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.028 sec. to 1.028 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.802175 ( -0.269559 0.2916 )
Norm@50keV : 8.34414E-03 ( -0.00141601 0.00138512 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.38 using 59 PHA bins.
# Reduced chi-squared = 1.007 for 57 degrees of freedom
# Null hypothesis probability = 4.609700e-01
Photon flux (15-150 keV) in 1 sec: 0.958927 ( -0.156621 0.157683 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.74294e-08 ( -1.57843e-08 1.58524e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.028 sec. to 1.028 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.209986 ( -0.808191 1.52539 )
Epeak [keV] : 181.860 ( -181.885 -181.885 )
Norm@50keV : 1.48534E-02 ( -0.0076023 0.0453767 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.64 using 59 PHA bins.
# Reduced chi-squared = 1.011 for 56 degrees of freedom
# Null hypothesis probability = 4.510627e-01
Photon flux (15-150 keV) in 1 sec: 0.938613 ( -0.161907 0.162587 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.52072e-08 ( -1.71901e-08 1.66361e-08 ) ergs/cm2
Time-resolved spectra
