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 -0.908 sec. to 7.296 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.30359 ( -0.0826502 0.0832992 )
Norm@50keV : 3.21766E-02 ( -0.00163143 0.0016301 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.41 using 59 PHA bins.
# Reduced chi-squared = 1.130 for 57 degrees of freedom
# Null hypothesis probability = 2.333203e-01
Photon flux (15-150 keV) in 8.204 sec: 3.84135 ( -0.2105 0.21109 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.60661e-06 ( -1.3542e-07 1.3557e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.908 sec. to 7.296 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.614702 ( -0.366232 0.399137 )
Epeak [keV] : 116.098 ( -22.8862 64.6692 )
Norm@50keV : 6.52679E-02 ( -0.0200062 0.0315426 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.42 using 59 PHA bins.
# Reduced chi-squared = 0.9539 for 56 degrees of freedom
# Null hypothesis probability = 5.731293e-01
Photon flux (15-150 keV) in 8.204 sec: 3.73346 ( -0.21708 0.21809 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.55803e-06 ( -1.40536e-07 1.40053e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.128 sec. to 0.872 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.04984 ( -0.118756 0.121411 )
Norm@50keV : 7.74170E-02 ( -0.00598253 0.00595978 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 81.37 using 59 PHA bins.
# Reduced chi-squared = 1.428 for 57 degrees of freedom
# Null hypothesis probability = 1.873043e-02
Photon flux (15-150 keV) in 1 sec: 0.255427 0.280324 0.215982 0.166025 0.130088 0.104953 8.76381E-02 7.57277E-02 6.74503E-02 6.15910E-02 5.73478E-02 5.41999E-02 5.18087E-02 4.99517E-02 4.84804E-02 4.72935E-02 4.63204E-02 4.55113E-02 4.48299E-02 4.42496E-02 4.33211E-02 4.26091E-02 4.20480E-02 4.11903E-02 4.05493E-02 3.97186E-02 3.76361E-02 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 8.22925e-07 ( -6.41203e-08 6.42719e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.128 sec. to 0.872 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.249077 ( -0.536303 0.611475 )
Epeak [keV] : 128.642 ( -32.1639 133.957 )
Norm@50keV : 0.174662 ( -0.0721079 0.14147 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 74.56 using 59 PHA bins.
# Reduced chi-squared = 1.331 for 56 degrees of freedom
# Null hypothesis probability = 4.927705e-02
Photon flux (15-150 keV) in 1 sec: 8.78846 ( -0.71857 0.72039 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.1169e-07 ( -6.67522e-08 6.63615e-08 ) ergs/cm2
Time-resolved spectra
