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 -1.424 sec. to 46.396 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.85199 ( -0.0650872 0.0646087 )
Norm@50keV : 8.59925E-03 ( -0.000290248 0.000289047 )
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#Fit statistic : Chi-Squared = 39.11 using 59 PHA bins.
# Reduced chi-squared = 0.6861 for 57 degrees of freedom
# Null hypothesis probability = 9.662173e-01
Photon flux (15-150 keV) in 47.82 sec: 1.20976 ( -0.04103 0.04118 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.78155e-06 ( -1.28213e-07 1.28837e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.424 sec. to 46.396 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.63286 ( -0.130203 0.269799 )
Epeak [keV] : 79.5191 ( -21.1259 -79.5196 )
Norm@50keV : 1.11393E-02 ( -0.00266357 0.00408512 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 36.94 using 59 PHA bins.
# Reduced chi-squared = 0.6596 for 56 degrees of freedom
# Null hypothesis probability = 9.769307e-01
Photon flux (15-150 keV) in 47.82 sec: 1.18816 ( -0.04758 0.04772 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.69105e-06 ( -1.64015e-07 1.63908e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.296 sec. to 0.704 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.48921 ( -0.115579 0.114568 )
Norm@50keV : 3.44780E-02 ( -0.00225542 0.00224376 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 42.67 using 59 PHA bins.
# Reduced chi-squared = 0.7486 for 57 degrees of freedom
# Null hypothesis probability = 9.208522e-01
Photon flux (15-150 keV) in 1 sec: 4.29194 ( -0.27189 0.27211 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.27703e-07 ( -2.38665e-08 2.41085e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.296 sec. to 0.704 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.27946 ( -0.270227 0.479661 )
Epeak [keV] : 167.559 ( -167.56 -167.56 )
Norm@50keV : 4.42049E-02 ( -0.0115964 0.0329083 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 42.01 using 59 PHA bins.
# Reduced chi-squared = 0.7501 for 56 degrees of freedom
# Null hypothesis probability = 9.173627e-01
Photon flux (15-150 keV) in 1 sec: 4.24465 ( -0.28955 0.28857 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.21048e-07 ( -2.77764e-08 2.74738e-08 ) ergs/cm2
Time-resolved spectra
