We present new measurements of the inclusive forward-backward
tt-bar production asymmetry, AFB, and its dependence on several
properties of the tt-bar system. The measurements are performed with
the full Tevatron data set recorded with the CDF II detector during
pp-bar collisions at sqrt(s)=1.96???TeV, corresponding to an integrated
luminosity of 9.4???fb-1. We measure the asymmetry using the rapi+dity
difference Delta y=yt - yt-bar. Parton-level results are derived,
yielding an inclusive asymmetry of 0.164 +/- 0.047(stat+syst). We
establish an approximately linear dependence of AFB on the top-quark
pair mass Mtt-bar and the rapi+dity difference Delta y at detector and
parton levels. Assuming the standard model, the probabilities to observe
the measured values or larger for the detector-level dependencies are
7.4??10-3 and 2.2??10-3 for Mtt-bar and Delta y respectively. Lastly,
we study the dependence of the asymmetry on the transverse momentum of
the tt-bar system at the detector level. These results are consistent
with previous lower-precision measurements and provide additional
quantification of the functional dependencies of the asymmetry.
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Updated: Tuesday, 2013 June 04 12:35:12 CDT automatically from input from Barbara Hehner