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 -26.352 sec. to 47.648 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.47839 ( -0.267109 0.262726 )
Norm@50keV : 7.56398E-04 ( -0.000120059 0.000118062 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.16 using 59 PHA bins.
# Reduced chi-squared = 1.020 for 57 degrees of freedom
# Null hypothesis probability = 4.322053e-01
Photon flux (15-150 keV) in 74 sec: 9.38922E-02 ( -0.0138288 0.0138328 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.32993e-07 ( -9.36929e-08 9.61245e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -26.352 sec. to 47.648 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.30305 ( )
Epeak [keV] : 181.786 ( )
Norm@50keV : 9.42973E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.07 using 59 PHA bins.
# Reduced chi-squared = 1.037 for 56 degrees of freedom
# Null hypothesis probability = 3.988145e-01
Photon flux (15-150 keV) in 74 sec: 9.31837E-02 ( -0.0144272 0.0071883 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.22086e-07 ( -1.12804e-07 1.04589e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 2.648 sec. to 3.648 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.694609 ( -0.751056 0.911412 )
Norm@50keV : 2.52370E-03 ( -0.00114544 0.00103294 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.80 using 59 PHA bins.
# Reduced chi-squared = 0.8210 for 57 degrees of freedom
# Null hypothesis probability = 8.304583e-01
Photon flux (15-150 keV) in 1 sec: 0.291839 ( -0.114466 0.116347 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.0883e-08 ( -1.24774e-08 1.27093e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.648 sec. to 3.648 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.68612 ( 0.44179 10.4284 )
Epeak [keV] : 9997.86 ( -9997.96 -9997.96 )
Norm@50keV : 2.54290E-03 ( -0.00105818 10.4617 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.80 using 59 PHA bins.
# Reduced chi-squared = 0.8357 for 56 degrees of freedom
# Null hypothesis probability = 8.046751e-01
Photon flux (15-150 keV) in 1 sec: 0.292206 ( -0.14357 0.114931 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.08994e-08 ( -1.05959e-08 1.15538e-08 ) ergs/cm2
Time-resolved spectra
