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 -21.648 sec. to 69.864 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.47306 ( -0.0442169 0.0442559 )
Norm@50keV : 8.27817E-03 ( -0.000200673 0.000200672 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 74.04 using 59 bins.
Reduced chi-squared = 1.29895
# Null hypothesis probability of 6.41e-02 with 57 degrees of freedom
Photon flux (15-150 keV) in 91.51 sec: 1.02616 ( -0.027324 0.02739 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.22002e-06 ( -1.84138e-07 1.84528e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -21.648 sec. to 69.864 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.912555 ( -0.188372 0.196832 )
Epeak [keV] : 105.273 ( -14.1585 25.9435 )
Norm@50keV : 1.50374E-02 ( -0.00266651 0.00340184 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 46.03 using 59 bins.
Reduced chi-squared = 0.821964
# Null hypothesis probability of 8.27e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 91.51 sec: 0.987958 ( -0.029675 0.029772 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.95759e-06 ( -2.0456e-07 2.04317e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.260 sec. to 1.260 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.10202 ( -0.12377 0.125491 )
Norm@50keV : 2.89143E-02 ( -0.00216399 0.00216222 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 48.70 using 59 bins.
Reduced chi-squared = 0.854386
# Null hypothesis probability of 7.75e-01 with 57 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 3.35453 ( -0.25714 0.25738 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.02141e-07 ( -2.46557e-08 2.47779e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.260 sec. to 1.260 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.741878 ( -0.413886 0.545989 )
Epeak [keV] : 192.357 ( -84.8734 -192.358 )
Norm@50keV : 4.27385E-02 ( -0.015096 0.0330887 )
------------------------------------------------------------
#Fit statistic : Chi-Squared 47.13 using 59 bins.
Reduced chi-squared = 0.841607
# Null hypothesis probability of 7.95e-01 with 56 degrees of freedom
Photon flux (15-150 keV) in 1 sec: 3.32156 ( -0.26134 0.26134 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.97208e-07 ( -2.62076e-08 2.59166e-08 ) ergs/cm2
Time-resolved spectra
