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 -15.064 sec. to 48.936 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.06084 ( -0.420964 0.476325 )
Norm@50keV : 1.40789E-03 ( -0.000347816 0.000331335 )
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#Fit statistic : Chi-Squared = 57.78 using 59 PHA bins.
# Reduced chi-squared = 1.014 for 57 degrees of freedom
# Null hypothesis probability = 4.462443e-01
Photon flux (15-150 keV) in 64 sec: 0.162742 ( -0.040865 0.041461 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.54291e-07 ( -2.18339e-07 2.18552e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -15.064 sec. to 48.936 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.06836 ( -0.412082 0.545731 )
Epeak [keV] : 9999.30 ( -9999.36 -9999.36 )
Norm@50keV : 1.41927E-03 ( -0.000316964 0.00224114 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.79 using 59 PHA bins.
# Reduced chi-squared = 1.032 for 56 degrees of freedom
# Null hypothesis probability = 4.088315e-01
Photon flux (15-150 keV) in 64 sec: 0.165354 ( -0.054527 0.050188 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.5737e-07 ( -2.73962e-07 2.73409e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -7.564 sec. to -6.564 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.346917 ( 0.378549 0.378549 )
Norm@50keV : 1.65320E-03 ( -0.00166575 0.00236594 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.61 using 59 PHA bins.
# Reduced chi-squared = 1.046 for 57 degrees of freedom
# Null hypothesis probability = 3.807502e-01
Photon flux (15-150 keV) in 1 sec: 0.203161 ( -0.203161 0.262458 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.40968e-08 ( 1 2.45977e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -7.564 sec. to -6.564 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 9.99947 ( -18.4408 -9.99995 )
Epeak [keV] : 79.5069 ( -26.7627 119.899 )
Norm@50keV : 5.19084 ( -5.08152 359.292 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.72 using 59 PHA bins.
# Reduced chi-squared = 1.031 for 56 degrees of freedom
# Null hypothesis probability = 4.114903e-01
Photon flux (15-150 keV) in 1 sec: 0.189943 ( -0.189943 0.216917 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.20328e-08 ( -1.7046e-08 2.37434e-08 ) ergs/cm2
Time-resolved spectra
