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 -2.968 sec. to 159.104 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.67882 ( -0.0919559 0.0909684 )
Norm@50keV : 3.16760E-03 ( -0.000171242 0.000170453 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.03 using 59 PHA bins.
# Reduced chi-squared = 0.9479 for 57 degrees of freedom
# Null hypothesis probability = 5.871863e-01
Photon flux (15-150 keV) in 162.1 sec: 0.417645 ( -0.021951 0.021984 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.76324e-06 ( -2.71004e-07 2.72608e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.968 sec. to 159.104 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.961076 ( -0.398639 0.441266 )
Epeak [keV] : 69.1265 ( -11.0062 28.5345 )
Norm@50keV : 7.46930E-03 ( -0.00278415 0.00509137 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.88 using 59 PHA bins.
# Reduced chi-squared = 0.7836 for 56 degrees of freedom
# Null hypothesis probability = 8.801393e-01
Photon flux (15-150 keV) in 162.1 sec: 0.402107 ( -0.023464 0.023474 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.47871e-06 ( -3.09699e-07 3.12034e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 88.152 sec. to 89.152 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.84009 ( -0.385057 0.356352 )
Norm@50keV : 1.03803E-02 ( -0.00245187 0.00231256 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.45 using 59 PHA bins.
# Reduced chi-squared = 1.254 for 57 degrees of freedom
# Null hypothesis probability = 9.425356e-02
Photon flux (15-150 keV) in 1 sec: 1.45330 ( -0.27305 0.2731 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.54751e-08 ( -2.18035e-08 2.23832e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 88.152 sec. to 89.152 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.858 ( -0.370415 0.70621 )
Epeak [keV] : 9999.36 ( )
Norm@50keV : 1.03135E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.46 using 59 PHA bins.
# Reduced chi-squared = 1.276 for 56 degrees of freedom
# Null hypothesis probability = 7.978648e-02
Photon flux (15-150 keV) in 1 sec: 1.46164 ( -0.28115 0.26667 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.71649e-08 ( -3.44007e-08 4.11801e-08 ) ergs/cm2
Time-resolved spectra
