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 -17.688 sec. to 329.352 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.64655 ( -0.277596 0.26572 )
Norm@50keV : 3.54460E-04 ( -5.97004e-05 5.79093e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.07 using 59 PHA bins.
# Reduced chi-squared = 1.089 for 57 degrees of freedom
# Null hypothesis probability = 3.002980e-01
Photon flux (15-150 keV) in 347 sec: 4.62330E-02 ( -0.0066548 0.0066555 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.14448e-06 ( -2.03396e-07 2.09333e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -17.688 sec. to 329.352 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.64494 ( -1.32145 0.91231 )
Epeak [keV] : 9998.34 ( -9998.7 -9998.71 )
Norm@50keV : 3.55206E-04 ( -6.00653e-05 0.000805908 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.07 using 59 PHA bins.
# Reduced chi-squared = 1.108 for 56 degrees of freedom
# Null hypothesis probability = 2.687361e-01
Photon flux (15-150 keV) in 347 sec: 4.63284E-02 ( -0.0070291 0.0066423 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.15064e-06 ( -2.40541e-07 2.10519e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.444 sec. to 1.444 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.97901 ( -0.365757 0.400203 )
Norm@50keV : 5.71258E-03 ( -0.00121827 0.00120587 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.82 using 59 PHA bins.
# Reduced chi-squared = 1.014 for 57 degrees of freedom
# Null hypothesis probability = 4.449098e-01
Photon flux (15-150 keV) in 1 sec: 0.657019 ( -0.141317 0.142198 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.22458e-08 ( -1.40233e-08 1.41888e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.444 sec. to 1.444 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -2.33466 ( -3.63884 2.26922 )
Epeak [keV] : 105.201 ( )
Norm@50keV : 3.30838E-04 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.40 using 59 PHA bins.
# Reduced chi-squared = 1.007 for 56 degrees of freedom
# Null hypothesis probability = 4.597690e-01
Photon flux (15-150 keV) in 1 sec: 0.657387 ( -0.14152 0.141165 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.23362e-08 ( -1.52515e-08 1.26947e-08 ) ergs/cm2
Time-resolved spectra
