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 -0.840 sec. to 51.752 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.30624 ( -0.245172 0.254288 )
Norm@50keV : 3.16003E-03 ( -0.000415803 0.000413227 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.55 using 59 PHA bins.
# Reduced chi-squared = 1.062 for 57 degrees of freedom
# Null hypothesis probability = 3.489874e-01
Photon flux (15-150 keV) in 52.59 sec: 0.377440 ( -0.055098 0.055537 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.63992e-06 ( -2.1932e-07 2.19605e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.840 sec. to 51.752 sec.
Spectral model in the cutoff power-law:
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Parameters : value lower 90% higher 90%
Photon index: -2.17276 ( -0.758243 1.20683 )
Epeak [keV] : 63.9331 ( )
Norm@50keV : 9.18171E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.87 using 59 PHA bins.
# Reduced chi-squared = 1.069 for 56 degrees of freedom
# Null hypothesis probability = 3.370578e-01
Photon flux (15-150 keV) in 52.59 sec: 0.377431 ( -0.055148 0.055499 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.64522e-06 ( -2.25036e-07 2.13887e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 8.204 sec. to 9.204 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.35843 ( -0.524517 0.558068 )
Norm@50keV : 1.01567E-02 ( -0.00298279 0.00296745 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.54 using 59 PHA bins.
# Reduced chi-squared = 1.062 for 57 degrees of freedom
# Null hypothesis probability = 3.494930e-01
Photon flux (15-150 keV) in 1 sec: 1.22575 ( -0.390432 0.3973 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.90239e-08 ( -2.98806e-08 3.00564e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 8.204 sec. to 9.204 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -3.18195 ( 3.17314 3.77641 )
Epeak [keV] : 326.621 ( )
Norm@50keV : 9.16063E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.12 using 59 PHA bins.
# Reduced chi-squared = 1.074 for 56 degrees of freedom
# Null hypothesis probability = 3.289239e-01
Photon flux (15-150 keV) in 1 sec: 1.22927 ( -0.405184 0.39524 ) ph/cm2/s
Energy fluence (15-150 keV) : 9.92773e-08 ( -3.24629e-08 2.78269e-08 ) ergs/cm2
Time-resolved spectra
