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 -0.780 sec. to 6.632 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.07922 ( -0.119947 0.121793 )
Norm@50keV : 6.72200E-03 ( -0.000454734 0.000454571 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.55 using 59 PHA bins.
# Reduced chi-squared = 0.7114 for 57 degrees of freedom
# Null hypothesis probability = 9.511406e-01
Photon flux (15-150 keV) in 7.412 sec: 0.778213 ( -0.053659 0.053709 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.24476e-07 ( -3.99408e-08 4.02469e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.780 sec. to 6.632 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.926333 ( -0.212869 0.50696 )
Epeak [keV] : 375.349 ( -375.408 -375.408 )
Norm@50keV : 7.95773E-03 ( -0.00161933 0.00574543 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.24 using 59 PHA bins.
# Reduced chi-squared = 0.7185 for 56 degrees of freedom
# Null hypothesis probability = 9.444286e-01
Photon flux (15-150 keV) in 7.412 sec: 0.773106 ( -0.055914 0.055672 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.18377e-07 ( -4.46855e-08 4.37386e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.256 sec. to 0.744 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.05757 ( -0.183376 0.187243 )
Norm@50keV : 1.23515E-02 ( -0.00131697 0.00131692 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 70.54 using 59 PHA bins.
# Reduced chi-squared = 1.237 for 57 degrees of freedom
# Null hypothesis probability = 1.073420e-01
Photon flux (15-150 keV) in 1 sec: 1.42738 ( -0.15325 0.15333 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.30954e-07 ( -1.61096e-08 1.63112e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.256 sec. to 0.744 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.721453 ( -0.428862 0.802624 )
Epeak [keV] : 197.373 ( -197.381 -197.381 )
Norm@50keV : 1.80899E-02 ( -0.007216 0.0256802 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 69.85 using 59 PHA bins.
# Reduced chi-squared = 1.247 for 56 degrees of freedom
# Null hypothesis probability = 1.010006e-01
Photon flux (15-150 keV) in 1 sec: 1.40837 ( -0.15881 0.15818 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.2721e-07 ( -1.8312e-08 1.79811e-08 ) ergs/cm2
Time-resolved spectra
