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 -15.624 sec. to 64.376 sec.
Spectral model in power-law:
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Parameters : value lower 90% higher 90%
Photon index: -1.80167 ( -0.0944541 0.0932117 )
Norm@50keV : 8.70290E-03 ( -0.000490364 0.00048775 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.29 using 59 PHA bins.
# Reduced chi-squared = 1.128 for 57 degrees of freedom
# Null hypothesis probability = 2.364580e-01
Photon flux (15-150 keV) in 80 sec: 1.20008 ( -0.06653 0.06667 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.41018e-06 ( -3.66795e-07 3.68424e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -15.624 sec. to 64.376 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.32792 ( -0.359271 0.39216 )
Epeak [keV] : 68.9261 ( -13.494 60.5394 )
Norm@50keV : 1.52840E-02 ( -0.00519353 0.00882503 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.05 using 59 PHA bins.
# Reduced chi-squared = 1.055 for 56 degrees of freedom
# Null hypothesis probability = 3.645945e-01
Photon flux (15-150 keV) in 80 sec: 1.17222 ( -0.0696 0.06969 ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 7.876 sec. to 8.876 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.70731 ( -0.254703 0.243935 )
Norm@50keV : 3.17388E-02 ( -0.0052145 0.005135 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 47.59 using 59 PHA bins.
# Reduced chi-squared = 0.8350 for 57 degrees of freedom
# Null hypothesis probability = 8.081899e-01
Photon flux (15-150 keV) in 1 sec: 4.22627 ( -0.65283 0.65365 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.93738e-07 ( -4.97267e-08 5.02474e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 7.876 sec. to 8.876 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.906174 ( -0.901436 1.17864 )
Epeak [keV] : 66.8422 ( -17.3541 -66.8429 )
Norm@50keV : 8.29813E-02 ( -0.0829793 0.245991 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 45.47 using 59 PHA bins.
# Reduced chi-squared = 0.8120 for 56 degrees of freedom
# Null hypothesis probability = 8.415292e-01
Photon flux (15-150 keV) in 1 sec: 4.14146 ( -0.66291 0.66263 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.83211e-07 ( -5.09641e-08 5.18239e-08 ) ergs/cm2
Time-resolved spectra
