Parity Nonconservation in Strong Interactions

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.

4 pages, 3 figures; v2 references added, typos in eqs. 13-15 corrected, Fig. 2 changed

References in corpus (2)

• On measurement of top polarization as a probe of $t\bar{t}$ production mechanisms at the LHC
• Tevatron Top $A_{FB}$ Versus LHC Top Physics

Cited by in corpus (3)

• Zero and one jet combined NLO analysis of the top quark forward-backward asymmetry
• Data driving the top quark forward--backward asymmetry with a lepton-based handle
• Spinning the Top