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 -5.284 sec. to 129.836 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.33212 ( -0.0476329 0.047855 )
Norm@50keV : 4.31470E-03 ( -0.000104787 0.000104732 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.61 using 59 PHA bins.
# Reduced chi-squared = 0.9580 for 57 degrees of freedom
# Null hypothesis probability = 5.654444e-01
Photon flux (15-150 keV) in 135.1 sec: 0.517927 ( -0.01391 0.013968 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.71709e-06 ( -1.46579e-07 1.46924e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -5.284 sec. to 129.836 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.33043 ( -0.0463028 0.0893692 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 4.32258E-03 ( -0.00010468 0.000423743 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.72 using 59 PHA bins.
# Reduced chi-squared = 0.9771 for 56 degrees of freedom
# Null hypothesis probability = 5.235897e-01
Photon flux (15-150 keV) in 135.1 sec: 0.522152 ( -0.018279 0.009582 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.75169e-06 ( -1.82846e-07 1.1057e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 2.228 sec. to 3.228 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.744502 ( -0.115558 0.118734 )
Norm@50keV : 2.38537E-02 ( -0.00157979 0.00156619 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.31 using 59 PHA bins.
# Reduced chi-squared = 0.9528 for 57 degrees of freedom
# Null hypothesis probability = 5.766764e-01
Photon flux (15-150 keV) in 1 sec: 2.74876 ( -0.17531 0.17561 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.85496e-07 ( -1.93377e-08 1.94128e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 2.228 sec. to 3.228 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.738233 ( -0.115303 0.121279 )
Epeak [keV] : 9999.35 ( -9999.36 -9999.36 )
Norm@50keV : 2.39681E-02 ( -0.00149821 0.0100607 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.33 using 59 PHA bins.
# Reduced chi-squared = 0.9702 for 56 degrees of freedom
# Null hypothesis probability = 5.381642e-01
Photon flux (15-150 keV) in 1 sec: 2.75142 ( -0.1849 0.17943 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.86108e-07 ( 0 0 ) ergs/cm2
Time-resolved spectra