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 -4.016 sec. to 14.288 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.940419 ( -0.218375 0.230551 )
Norm@50keV : 4.05613E-03 ( -0.000545238 0.000539011 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 56.67 using 59 bins.
Reduced chi-squared = 0.994211
# Null hypothesis probability of 4.87e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 18.3 sec: 0.465879 ( -0.062883 0.063273 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.20373e-07 ( -1.09436e-07 1.09859e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -4.016 sec. to 14.288 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.14331 ( -0.924723 1.20284 )
Epeak [keV] : 138.338 ( -51.7272 -138.338 )
Norm@50keV : 8.87224E-03 ( -0.00887224 0.018083 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 54.63 using 59 bins.
Reduced chi-squared = 0.975536
# Null hypothesis probability of 5.27e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 18.3 sec: 0.450376 ( -0.065646 0.06595 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.93618e-07 ( -1.17969e-07 1.16193e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 10.788 sec. to 11.788 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.42759 ( -0.445177 0.431443 )
Norm@50keV : 7.75943E-03 ( -0.00225183 0.00224027 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 57.87 using 59 bins.
Reduced chi-squared = 1.01526
# Null hypothesis probability of 4.43e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.950976 ( -0.27603 0.277144 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.45916e-08 ( -2.30533e-08 2.34951e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 10.788 sec. to 11.788 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 3.94952 ( -3.46898 -2.98095 )
Epeak [keV] : 54.8536 ( -10.9518 32.0207 )
Norm@50keV : 3.20078 ( -3.1648 3041.32 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 52.26 using 59 bins.
Reduced chi-squared = 0.933214
# Null hypothesis probability of 6.17e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 0.806341 ( -0.282722 0.313539 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.01381e-08 ( -2.12175e-08 2.63109e-08 ) ergs/cm2
Time-resolved spectra
