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 -8.280 sec. to 101.016 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.998425 ( -0.21367 0.221691 )
Norm@50keV : 1.23326E-03 ( -0.000147436 0.000146264 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.08 using 59 PHA bins.
# Reduced chi-squared = 1.124 for 57 degrees of freedom
# Null hypothesis probability = 2.421515e-01
Photon flux (15-150 keV) in 109.3 sec: 0.141972 ( -0.017301 0.017409 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.45858e-06 ( -1.8199e-07 1.82997e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -8.280 sec. to 101.016 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.865113 ( -0.328748 1.02251 )
Epeak [keV] : 513.471 ( -515.436 -515.436 )
Norm@50keV : 1.40260E-03 ( -0.000282275 0.00120944 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.01 using 59 PHA bins.
# Reduced chi-squared = 1.143 for 56 degrees of freedom
# Null hypothesis probability = 2.159257e-01
Photon flux (15-150 keV) in 109.3 sec: 0.140977 ( -0.018594 0.01717 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.45064e-06 ( -1.91077e-07 1.85498e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 1.036 sec. to 2.036 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.570049 ( -0.394375 0.444178 )
Norm@50keV : 6.68617E-03 ( -0.0019029 0.00184873 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 73.27 using 59 PHA bins.
# Reduced chi-squared = 1.285 for 57 degrees of freedom
# Null hypothesis probability = 7.213927e-02
Photon flux (15-150 keV) in 1 sec: 0.783451 ( -0.198339 0.20204 ) ph/cm2/s
Energy fluence (15-150 keV) : 8.67721e-08 ( -2.12738e-08 2.13464e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.036 sec. to 2.036 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 5.73035 ( -5.01646 -6.19823 )
Epeak [keV] : 85.2529 ( -12.1981 39.9639 )
Norm@50keV : 0.779664 ( -0.752959 18.8495 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.04 using 59 PHA bins.
# Reduced chi-squared = 1.161 for 56 degrees of freedom
# Null hypothesis probability = 1.908980e-01
Photon flux (15-150 keV) in 1 sec: 0.646072 ( -0.173968 0.205917 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.54779e-08 ( -2.15926e-08 2.36806e-08 ) ergs/cm2
Time-resolved spectra
