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 -6.408 sec. to 5.196 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.72491 ( -0.0922982 0.0910761 )
Norm@50keV : 1.36258E-02 ( -0.000755416 0.000752361 )
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#Fit statistic : Chi-Squared = 60.00 using 59 PHA bins.
# Reduced chi-squared = 1.053 for 57 degrees of freedom
# Null hypothesis probability = 3.675722e-01
Photon flux (15-150 keV) in 11.6 sec: 1.82577 ( -0.10073 0.10092 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.46103e-06 ( -8.38286e-08 8.40733e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -6.408 sec. to 5.196 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.961261 ( -0.39484 0.434067 )
Epeak [keV] : 67.7279 ( -9.67607 21.6706 )
Norm@50keV : 3.30991E-02 ( -0.0119584 0.0211368 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.20 using 59 PHA bins.
# Reduced chi-squared = 0.8607 for 56 degrees of freedom
# Null hypothesis probability = 7.613327e-01
Photon flux (15-150 keV) in 11.6 sec: 1.75870 ( -0.10601 0.1062 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.39351e-06 ( -9.07373e-08 9.1087e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 2.144 sec. to 3.144 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.56993 ( -0.13262 0.130668 )
Norm@50keV : 3.67945E-02 ( -0.00290336 0.00289516 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 33.77 using 59 PHA bins.
# Reduced chi-squared = 0.5924 for 57 degrees of freedom
# Null hypothesis probability = 9.938919e-01
Photon flux (15-150 keV) in 1 sec: 4.68544 ( -0.37905 0.37982 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.45478e-07 ( -2.89078e-08 2.90377e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.144 sec. to 3.144 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.13369 ( -0.489275 0.587438 )
Epeak [keV] : 106.504 ( -35.1493 -106.504 )
Norm@50keV : 5.96298E-02 ( -0.0242499 0.0523076 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 31.78 using 59 PHA bins.
# Reduced chi-squared = 0.5676 for 56 degrees of freedom
# Null hypothesis probability = 9.962451e-01
Photon flux (15-150 keV) in 1 sec: 4.60101 ( -0.39245 0.39305 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.39735e-07 ( -3.00644e-08 3.00251e-08 ) ergs/cm2
Time-resolved spectra
