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 -13.588 sec. to 25.324 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.62703 ( -0.206829 0.202389 )
Norm@50keV : 2.24986E-03 ( -0.000278374 0.000273608 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.40 using 59 PHA bins.
# Reduced chi-squared = 0.8140 for 57 degrees of freedom
# Null hypothesis probability = 8.410904e-01
Photon flux (15-150 keV) in 38.91 sec: 0.291601 ( -0.0329 0.032922 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.16246e-07 ( -1.07793e-07 1.09541e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -13.588 sec. to 25.324 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.62531 ( -0.786135 0.671384 )
Epeak [keV] : 9998.14 ( -9998.46 -9998.46 )
Norm@50keV : 2.25488E-03 ( -0.00148343 0.00309307 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.40 using 59 PHA bins.
# Reduced chi-squared = 0.8285 for 56 degrees of freedom
# Null hypothesis probability = 8.162696e-01
Photon flux (15-150 keV) in 38.91 sec: 0.291868 ( -0.033893 0.032878 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.17958e-07 ( -1.22003e-07 8.67347e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 2.084 sec. to 3.084 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.55049 ( -0.393505 0.378285 )
Norm@50keV : 6.85899E-03 ( -0.00176515 0.00173292 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.57 using 59 PHA bins.
# Reduced chi-squared = 0.9223 for 57 degrees of freedom
# Null hypothesis probability = 6.416616e-01
Photon flux (15-150 keV) in 1 sec: 0.868459 ( -0.210105 0.210251 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.45743e-08 ( -1.75903e-08 1.80124e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.084 sec. to 3.084 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.663571 ( -1.18526 2.11716 )
Epeak [keV] : 69.1877 ( -19.0834 -69.1879 )
Norm@50keV : 2.10638E-02 ( -0.0210635 0.311009 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.50 using 59 PHA bins.
# Reduced chi-squared = 0.9196 for 56 degrees of freedom
# Null hypothesis probability = 6.458207e-01
Photon flux (15-150 keV) in 1 sec: 0.855306 ( -0.211073 0.211394 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.04979e-08 ( -1.87408e-08 1.93475e-08 ) ergs/cm2
Time-resolved spectra
