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arXiv · 1108.2275

Parity Nonconservation in Strong Interactions

Vernon Barger·Wai-Yee Keung·Chiu-Tien Yu
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Abstract

For top-quarks produced via the subprocess $q\bar q\to t\bar t$, the longitudinal t-quark polarization ($P_{\parallel}$) vanishes in QCD. $P_{\parallel}$ can be measured by the angular distribution of the lepton in $t$-quark semileptonic decay. New physics contributions that are parity nonconserving will be manifest by non-vanishing $P_{\parallel}$, which may be large. We illustrate this with the s-channel exchange of a massive $X$-gluon with chiral quark couplings.

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Vernon Barger, Wai-Yee Keung, Chiu-Tien Yu. 2011-08-10. Parity Nonconservation in Strong Interactions. https://doi.org/10.1103/physrevd.85.056008

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