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 -6.528 sec. to 602.396 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.59279 ( -0.0348039 0.0348116 )
Norm@50keV : 3.45150E-03 ( -5.94145e-05 5.94104e-05 )
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#Fit statistic : Chi-Squared = 35.68 using 59 PHA bins.
# Reduced chi-squared = 0.6260 for 57 degrees of freedom
# Null hypothesis probability = 9.879358e-01
Photon flux (15-150 keV) in 608.9 sec: 0.442563 ( -0.009135 0.009176 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.96746e-05 ( -3.44856e-07 3.45494e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -6.528 sec. to 602.396 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.47135 ( -0.13195 0.141823 )
Epeak [keV] : 245.032 ( -101.299 -245.033 )
Norm@50keV : 3.90457E-03 ( -0.00046737 0.000587946 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 33.43 using 59 PHA bins.
# Reduced chi-squared = 0.5970 for 56 degrees of freedom
# Null hypothesis probability = 9.928183e-01
Photon flux (15-150 keV) in 608.9 sec: 0.437264 ( -0.01077 0.010845 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.94942e-05 ( -3.994e-07 1.99854e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 139.744 sec. to 140.744 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.20597 ( -0.131122 0.131823 )
Norm@50keV : 1.63617E-02 ( -0.00118001 0.00117857 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.67 using 59 PHA bins.
# Reduced chi-squared = 0.9064 for 57 degrees of freedom
# Null hypothesis probability = 6.747529e-01
Photon flux (15-150 keV) in 1 sec: 1.92217 ( -0.13994 0.1401 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.65737e-07 ( -1.38012e-08 1.39183e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 139.744 sec. to 140.744 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.20659 ( -0.127619 0.137102 )
Epeak [keV] : 9999.36 ( -9999.36 -9999.36 )
Norm@50keV : 1.64048E-02 ( -0.00118035 0.00579167 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.70 using 59 PHA bins.
# Reduced chi-squared = 0.9232 for 56 degrees of freedom
# Null hypothesis probability = 6.382355e-01
Photon flux (15-150 keV) in 1 sec: 1.92183 ( -0.14 0.14002 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.5437e-08 ( -4.48397e-09 4.2253e-09 ) ergs/cm2
Time-resolved spectra
