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 -3.420 sec. to 187.800 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.46657 ( -0.0651493 0.0653735 )
Norm@50keV : 6.34006E-03 ( -0.000235475 0.000235362 )
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#Fit statistic : Chi-Squared = 58.09 using 59 PHA bins.
# Reduced chi-squared = 1.019 for 57 degrees of freedom
# Null hypothesis probability = 4.348099e-01
Photon flux (15-150 keV) in 191.2 sec: 0.784606 ( -0.033184 0.033328 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.15669e-05 ( -4.3481e-07 4.34911e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -3.420 sec. to 187.800 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.087 ( -0.265004 0.28111 )
Epeak [keV] : 140.509 ( -36.0114 173.394 )
Norm@50keV : 9.28517E-03 ( -0.00212201 0.0029175 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.99 using 59 PHA bins.
# Reduced chi-squared = 0.9284 for 56 degrees of freedom
# Null hypothesis probability = 6.273298e-01
Photon flux (15-150 keV) in 191.2 sec: 0.764927 ( -0.035526 0.035726 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.14035e-05 ( -4.52641e-07 4.51406e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 107.852 sec. to 108.852 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.19431 ( -0.206099 0.211488 )
Norm@50keV : 2.99622E-02 ( -0.00375427 0.00373633 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.09 using 59 PHA bins.
# Reduced chi-squared = 0.9139 for 57 degrees of freedom
# Null hypothesis probability = 6.592724e-01
Photon flux (15-150 keV) in 1 sec: 3.51417 ( -0.46769 0.471 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.04502e-07 ( -3.86622e-08 3.87318e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 107.852 sec. to 108.852 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.65135 ( -0.64023 1.03482 )
Epeak [keV] : 147.577 ( )
Norm@50keV : 5.14584E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 50.93 using 59 PHA bins.
# Reduced chi-squared = 0.9094 for 56 degrees of freedom
# Null hypothesis probability = 6.668311e-01
Photon flux (15-150 keV) in 1 sec: 3.43315 ( -0.4837 0.48715 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.00331e-07 ( -4.01474e-08 3.97247e-08 ) ergs/cm2
Time-resolved spectra
