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 -2.136 sec. to 13.888 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.92594 ( -0.244537 0.230157 )
Norm@50keV : 4.04506E-03 ( -0.000581736 0.000560972 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.51 using 59 PHA bins.
# Reduced chi-squared = 1.167 for 57 degrees of freedom
# Null hypothesis probability = 1.821165e-01
Photon flux (15-150 keV) in 16.02 sec: 0.587045 ( -0.070793 0.07097 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.96091e-07 ( -8.1879e-08 8.29442e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -2.136 sec. to 13.888 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.52399 ( -0.22335 0.880404 )
Epeak [keV] : 187.437 ( )
Norm@50keV : 2.04749E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.32 using 59 PHA bins.
# Reduced chi-squared = 1.166 for 56 degrees of freedom
# Null hypothesis probability = 1.845287e-01
Photon flux (15-150 keV) in 16.02 sec: 0.588747 ( -0.109808 0.07068 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.74887e-07 ( -1.31644e-07 8.58557e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.508 sec. to 2.508 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.49949 ( -0.505545 0.494606 )
Norm@50keV : 7.72026E-03 ( -0.00217869 0.00215863 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.01 using 59 PHA bins.
# Reduced chi-squared = 0.9476 for 57 degrees of freedom
# Null hypothesis probability = 5.878833e-01
Photon flux (15-150 keV) in 1 sec: 0.963683 ( -0.277415 0.279677 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.32538e-08 ( -2.19547e-08 2.23247e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.508 sec. to 2.508 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.595282 ( -5.59504 0.556714 )
Epeak [keV] : 77.3895 ( )
Norm@50keV : 2.19550E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.80 using 59 PHA bins.
# Reduced chi-squared = 0.9607 for 56 degrees of freedom
# Null hypothesis probability = 5.587196e-01
Photon flux (15-150 keV) in 1 sec: 0.916924 ( -0.437457 0.307486 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.74109e-08 ( -3.34609e-08 2.552e-08 ) ergs/cm2
Time-resolved spectra
