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 -0.032 sec. to 1.340 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.83746 ( -0.21819 0.206817 )
Norm@50keV : 1.46422E-02 ( -0.00211033 0.00206677 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 57.93 using 59 PHA bins.
# Reduced chi-squared = 1.016 for 57 degrees of freedom
# Null hypothesis probability = 4.408899e-01
Photon flux (15-150 keV) in 1.372 sec: 2.04783 ( -0.25549 0.25561 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.84784e-07 ( -2.64789e-08 2.68594e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.032 sec. to 1.340 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.10545 ( -0.800794 0.994946 )
Epeak [keV] : 55.0858 ( -16.1878 -55.0858 )
Norm@50keV : 3.71705E-02 ( -0.0231994 0.094306 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.50 using 59 PHA bins.
# Reduced chi-squared = 0.9912 for 56 degrees of freedom
# Null hypothesis probability = 4.935501e-01
Photon flux (15-150 keV) in 1.372 sec: 2.00844 ( -0.2594 0.25937 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.75591e-07 ( -2.81551e-08 2.8749e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -0.034 sec. to 0.966 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.73956 ( -0.226995 0.217348 )
Norm@50keV : 1.69291E-02 ( -0.00249655 0.00245338 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.72 using 59 PHA bins.
# Reduced chi-squared = 0.9775 for 57 degrees of freedom
# Null hypothesis probability = 5.233018e-01
Photon flux (15-150 keV) in 1 sec: 2.28046 ( -0.30626 0.30647 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.56333e-07 ( -2.36211e-08 2.38941e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.034 sec. to 0.966 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.16136 ( -0.727132 1.0196 )
Epeak [keV] : 67.2229 ( -22.2942 -67.2229 )
Norm@50keV : 3.49522E-02 ( -0.0197253 0.0899563 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.30 using 59 PHA bins.
# Reduced chi-squared = 0.9697 for 56 degrees of freedom
# Null hypothesis probability = 5.394361e-01
Photon flux (15-150 keV) in 1 sec: 2.24953 ( -0.31004 0.30993 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.50487e-07 ( -2.54093e-08 2.54714e-08 ) ergs/cm2
Time-resolved spectra
