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 -21.816 sec. to 13.000 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.75914 ( -0.175926 0.169665 )
Norm@50keV : 2.07772E-03 ( -0.000244199 0.000240883 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.76 using 59 PHA bins.
# Reduced chi-squared = 1.031 for 57 degrees of freedom
# Null hypothesis probability = 4.107819e-01
Photon flux (15-150 keV) in 34.82 sec: 0.281908 ( -0.028606 0.028614 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.67357e-07 ( -8.02611e-08 8.17417e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -21.816 sec. to 13.000 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.0665121 ( -0.926106 1.18272 )
Epeak [keV] : 48.5278 ( -6.70072 8.22668 )
Norm@50keV : 1.88750E-02 ( -0.0188772 0.0706181 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.22 using 59 PHA bins.
# Reduced chi-squared = 0.8432 for 56 degrees of freedom
# Null hypothesis probability = 7.920156e-01
Photon flux (15-150 keV) in 34.82 sec: 0.266217 ( -0.029455 0.029566 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.74857e-07 ( -8.09008e-08 8.89602e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 2.740 sec. to 3.740 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.65938 ( -0.453788 0.417728 )
Norm@50keV : 5.98108E-03 ( -0.00160672 0.00150309 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.29 using 59 PHA bins.
# Reduced chi-squared = 1.181 for 57 degrees of freedom
# Null hypothesis probability = 1.653594e-01
Photon flux (15-150 keV) in 1 sec: 0.783444 ( -0.172347 0.172354 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.55815e-08 ( -1.52829e-08 1.58106e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.740 sec. to 3.740 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.24371 ( -0.767739 1.4725 )
Epeak [keV] : 90.6312 ( )
Norm@50keV : 3.02449E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.17 using 59 PHA bins.
# Reduced chi-squared = 1.200 for 56 degrees of freedom
# Null hypothesis probability = 1.457616e-01
Photon flux (15-150 keV) in 1 sec: 0.621499 ( -0.26491 0.182075 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.88562e-08 ( -1.57792e-08 9.73974e-09 ) ergs/cm2
Time-resolved spectra
