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 -6.080 sec. to 3.136 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.32094 ( -0.243463 0.224106 )
Norm@50keV : 3.79747E-03 ( -0.000648869 0.000636276 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 49.10 using 59 PHA bins.
# Reduced chi-squared = 0.8615 for 57 degrees of freedom
# Null hypothesis probability = 7.622584e-01
Photon flux (15-150 keV) in 9.216 sec: 0.671536 ( -0.074261 0.074261 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.35832e-07 ( -4.57756e-08 4.71801e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -6.080 sec. to 3.136 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.60404 ( -0.410979 1.67641 )
Epeak [keV] : 20.0153 ( )
Norm@50keV : 1.07209E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.95 using 59 PHA bins.
# Reduced chi-squared = 0.8563 for 56 degrees of freedom
# Null hypothesis probability = 7.692595e-01
Photon flux (15-150 keV) in 9.216 sec: 0.670693 ( -0.073766 0.075477 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.340 sec. to 0.660 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.62671 ( -0.211092 0.205778 )
Norm@50keV : 1.40772E-02 ( -0.00187235 0.00185385 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.32 using 59 PHA bins.
# Reduced chi-squared = 1.006 for 57 degrees of freedom
# Null hypothesis probability = 4.631439e-01
Photon flux (15-150 keV) in 1 sec: 1.82434 ( -0.23394 0.23425 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.31262e-07 ( -1.83994e-08 1.85753e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.340 sec. to 0.660 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.86492 ( -0.818517 1.00529 )
Epeak [keV] : 72.8582 ( -20.1085 -72.8581 )
Norm@50keV : 3.49781E-02 ( -0.0214037 0.0783594 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.82 using 59 PHA bins.
# Reduced chi-squared = 0.9790 for 56 degrees of freedom
# Null hypothesis probability = 5.194040e-01
Photon flux (15-150 keV) in 1 sec: 1.78192 ( -0.23937 0.23919 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.25594e-07 ( -1.93878e-08 1.96205e-08 ) ergs/cm2
Time-resolved spectra
