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 -1.496 sec. to 179.080 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.03655 ( -0.0367046 0.0365574 )
Norm@50keV : 1.24314E-02 ( -0.000209102 0.000209085 )
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#Fit statistic : Chi-Squared = 48.38 using 59 PHA bins.
# Reduced chi-squared = 0.8488 for 57 degrees of freedom
# Null hypothesis probability = 7.848226e-01
Photon flux (15-150 keV) in 180.6 sec: 1.89689 ( -0.04454 0.04494 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.07538e-05 ( -3.50655e-07 3.50801e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.496 sec. to 179.080 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.33242 ( -0.105842 0.148298 )
Epeak [keV] : 134.112 ( -39.0985 24.1974 )
Norm@50keV : 9.47830E-03 ( -0.000861786 0.00107307 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 33.99 using 59 PHA bins.
# Reduced chi-squared = 0.6069 for 56 degrees of freedom
# Null hypothesis probability = 9.912074e-01
Photon flux (15-150 keV) in 180.6 sec: 1.83976 ( -0.07162 0.07295 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.88286e-05 ( -1.33147e-06 1.45556e-06 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -1.324 sec. to -0.324 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.59796 ( -0.10353 0.10219 )
Norm@50keV : 8.94811E-02 ( -0.00544234 0.00542329 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.44 using 59 PHA bins.
# Reduced chi-squared = 0.9201 for 57 degrees of freedom
# Null hypothesis probability = 6.464515e-01
Photon flux (15-150 keV) in 1 sec: 11.4918 ( -0.7037 0.7048 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.37163e-07 ( -5.42022e-08 5.44163e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.324 sec. to -0.324 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.38245 ( -0.269338 0.429706 )
Epeak [keV] : 147.910 ( -67.1274 -147.914 )
Norm@50keV : 0.114506 ( -0.0292836 0.0705796 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.60 using 59 PHA bins.
# Reduced chi-squared = 0.9214 for 56 degrees of freedom
# Null hypothesis probability = 6.420733e-01
Photon flux (15-150 keV) in 1 sec: 11.3880 ( -0.7259 0.7292 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.27504e-07 ( -5.76648e-08 5.73263e-08 ) ergs/cm2
Time-resolved spectra
