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 22.553 sec. to 51.353 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.02774 ( -0.32631 0.295237 )
Norm@50keV : 1.05098E-03 ( -0.000222612 0.000212377 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.42 using 59 PHA bins.
# Reduced chi-squared = 0.7617 for 57 degrees of freedom
# Null hypothesis probability = 9.076623e-01
Photon flux (15-150 keV) in 28.8 sec: 0.159704 ( -0.023743 0.023743 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.79636e-07 ( -5.29767e-08 5.49464e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 22.553 sec. to 51.353 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.3396 ( -0.165383 1.20198 )
Epeak [keV] : 130.619 ( )
Norm@50keV : 7.21232E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.05 using 59 PHA bins.
# Reduced chi-squared = 0.7687 for 56 degrees of freedom
# Null hypothesis probability = 8.977901e-01
Photon flux (15-150 keV) in 28.8 sec: 0.140239 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 2.6182e-07 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 22.853 sec. to 23.853 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.34096 ( -0.172254 0.17161 )
Norm@50keV : 1.13911E-02 ( -0.00117672 0.00117258 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.89 using 59 PHA bins.
# Reduced chi-squared = 1.138 for 57 degrees of freedom
# Null hypothesis probability = 2.210114e-01
Photon flux (15-150 keV) in 1 sec: 1.36979 ( -0.14249 0.14266 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.11496e-07 ( -1.27658e-08 1.28667e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 22.853 sec. to 23.853 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.633827 ( -0.696886 0.840734 )
Epeak [keV] : 101.986 ( -30.5343 972.454 )
Norm@50keV : 2.50277E-02 ( -0.013303 0.0367269 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.88 using 59 PHA bins.
# Reduced chi-squared = 1.105 for 56 degrees of freedom
# Null hypothesis probability = 2.742825e-01
Photon flux (15-150 keV) in 1 sec: 1.33274 ( -0.14844 0.14752 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.07137e-07 ( -1.36524e-08 1.36861e-08 ) ergs/cm2
Time-resolved spectra
