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 -0.328 sec. to 43.420 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.28538 ( -0.0680927 0.0683079 )
Norm@50keV : 8.09523E-03 ( -0.000302179 0.000302175 )
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#Fit statistic : Chi-Squared = 48.77 using 59 PHA bins.
# Reduced chi-squared = 0.8556 for 57 degrees of freedom
# Null hypothesis probability = 7.728952e-01
Photon flux (15-150 keV) in 43.75 sec: 0.963239 ( -0.037976 0.038041 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.51284e-06 ( -1.42851e-07 1.43264e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.328 sec. to 43.420 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.0185 ( -0.270552 0.284828 )
Epeak [keV] : 201.645 ( -76.5348 4411.34 )
Norm@50keV : 1.07585E-02 ( -0.00239631 0.00369611 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.87 using 59 PHA bins.
# Reduced chi-squared = 0.8191 for 56 degrees of freedom
# Null hypothesis probability = 8.309642e-01
Photon flux (15-150 keV) in 43.75 sec: 0.948807 ( -0.040486 0.040535 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.45277e-06 ( -1.56689e-07 1.5574e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.128 sec. to 1.128 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.06733 ( -0.107177 0.107926 )
Norm@50keV : 4.39965E-02 ( -0.00274632 0.00274566 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.65 using 59 PHA bins.
# Reduced chi-squared = 0.7132 for 57 degrees of freedom
# Null hypothesis probability = 9.499147e-01
Photon flux (15-150 keV) in 1 sec: 5.08836 ( -0.32261 0.32277 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.64954e-07 ( -3.26493e-08 3.2806e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.128 sec. to 1.128 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.906133 ( -0.21407 0.436374 )
Epeak [keV] : 380.265 ( -380.266 -380.266 )
Norm@50keV : 5.22550E-02 ( -0.0104771 0.0296523 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 40.20 using 59 PHA bins.
# Reduced chi-squared = 0.7178 for 56 degrees of freedom
# Null hypothesis probability = 9.449950e-01
Photon flux (15-150 keV) in 1 sec: 1.35382 ( -0.486639 0.3071 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.61636e-07 ( -3.40928e-08 3.38941e-08 ) ergs/cm2
Time-resolved spectra
