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 0.220 sec. to 57.504 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.11417 ( -0.149131 0.152933 )
Norm@50keV : 2.41130E-03 ( -0.000212534 0.000211754 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.52 using 59 PHA bins.
# Reduced chi-squared = 1.167 for 57 degrees of freedom
# Null hypothesis probability = 1.820281e-01
Photon flux (15-150 keV) in 57.28 sec: 0.280090 ( -0.025825 0.025943 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.43778e-06 ( -1.30125e-07 1.30679e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.220 sec. to 57.504 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.443211 ( -0.635214 0.75866 )
Epeak [keV] : 137.638 ( -43.0299 854.497 )
Norm@50keV : 4.66681E-03 ( -0.00213419 0.00470512 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.25 using 59 PHA bins.
# Reduced chi-squared = 1.129 for 56 degrees of freedom
# Null hypothesis probability = 2.357384e-01
Photon flux (15-150 keV) in 57.28 sec: 0.270787 ( -0.027473 0.027428 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.40082e-06 ( -1.37213e-07 1.36635e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 5.584 sec. to 6.584 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.712326 ( -0.378625 0.430426 )
Norm@50keV : 7.14601E-03 ( -0.00184707 0.00176648 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.66 using 59 PHA bins.
# Reduced chi-squared = 0.9239 for 57 degrees of freedom
# Null hypothesis probability = 6.383156e-01
Photon flux (15-150 keV) in 1 sec: 0.825226 ( -0.194694 0.197784 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.67541e-08 ( -1.92593e-08 1.92835e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 5.584 sec. to 6.584 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.0488861 ( -1.41163 2.78815 )
Epeak [keV] : 178.805 ( -178.808 -178.808 )
Norm@50keV : 1.37840E-02 ( -0.00812492 0.0738335 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 52.02 using 59 PHA bins.
# Reduced chi-squared = 0.9290 for 56 degrees of freedom
# Null hypothesis probability = 6.261294e-01
Photon flux (15-150 keV) in 1 sec: 0.801461 ( -0.202674 0.204069 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.58045e-08 ( -1.98142e-08 1.96148e-08 ) ergs/cm2
Time-resolved spectra
