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 -51.748 sec. to 59.380 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.27033 ( -0.0415707 0.0416918 )
Norm@50keV : 6.42151E-03 ( -0.00014019 0.000140054 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.26 using 59 PHA bins.
# Reduced chi-squared = 0.6537 for 57 degrees of freedom
# Null hypothesis probability = 9.800420e-01
Photon flux (15-150 keV) in 111.1 sec: 0.762081 ( -0.018298 0.018347 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.1032e-06 ( -1.60729e-07 1.60937e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -51.748 sec. to 59.380 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.11926 ( -0.0734339 0.170199 )
Epeak [keV] : 340.686 ( -148.392 -340.689 )
Norm@50keV : 7.45783E-03 ( -0.000844095 0.00132833 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 34.81 using 59 PHA bins.
# Reduced chi-squared = 0.6216 for 56 degrees of freedom
# Null hypothesis probability = 9.882856e-01
Photon flux (15-150 keV) in 111.1 sec: 0.753525 ( -0.020324 0.020436 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.04132e-06 ( -1.74839e-07 1.74143e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -33.468 sec. to -32.468 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.10914 ( -0.0745419 0.0748868 )
Norm@50keV : 4.52392E-02 ( -0.00188758 0.0018872 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 44.02 using 59 PHA bins.
# Reduced chi-squared = 0.7723 for 57 degrees of freedom
# Null hypothesis probability = 8.959240e-01
Photon flux (15-150 keV) in 1 sec: 5.25219 ( -0.22456 0.22473 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.71672e-07 ( -2.20578e-08 2.21268e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -33.468 sec. to -32.468 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.917082 ( -0.223566 0.292646 )
Epeak [keV] : 316.808 ( -316.808 -316.808 )
Norm@50keV : 5.53485E-02 ( -0.0115679 0.0191703 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 42.61 using 59 PHA bins.
# Reduced chi-squared = 0.7609 for 56 degrees of freedom
# Null hypothesis probability = 9.063593e-01
Photon flux (15-150 keV) in 1 sec: 5.20682 ( -0.23346 0.23346 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.66692e-07 ( -2.34203e-08 2.33011e-08 ) ergs/cm2
Time-resolved spectra
