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Transverse Tau Polarization in Decays of the Top and Bottom Quarks in the Weinberg Model of CP Non-conservation

D. Atwood G. Eilam A. Soni
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Abstract

We show that the transverse polarization asymmetry of the $τ$-lepton in the decay $t\rightarrow b τν$ is extremely sensitive to CP violating phases arising from the charged Higgs exchange in the Weinberg model of CP non-conservation. Qualitatively, the polarization asymmetries are enhanced over rate or energy asymmetries by a factor of $\approx {m_t\over m_τ}\approx O(100)$. Thus for optimal values of the parameters the method requires $\approx 10^4$ top pairs to be observable rather than $10^7$ needed for rate or energy asymmetries. We also examine $τ$ polarization in b decays via $b \rightarrow c ντ$ and find that it can also be very effective in constraining the CP violation parameters of the extended Higgs sector.

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D. Atwood G. Eilam A. Soni. 1993-03-16. Transverse Tau Polarization in Decays of the Top and Bottom Quarks in the Weinberg Model of CP Non-conservation. https://doi.org/10.1103/physrevlett.71.492

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