Compositeness and the asymmetries of leptons at the Z^0 peak

R. Diaz; R. Martinez; J. -Alexis Rodriguez

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arXiv · hep-ph/9710535

Compositeness and the asymmetries of leptons at the Z^0 peak

R. Diaz·R. Martinez·J. -Alexis Rodriguez

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Abstract

We study the effects on the leptonic asymmetries A_{FB}, A_{pol} and A_{LR} coming from a model of compositeness. We consider the effects coming from the self-energies and the vertex correction to $Z l^+ l^-$. Thus we use the Altarelli parametrization of the oblique corrections. We get the asymptotic limits of these corrections in terms of the parameters $(m^*, Λ, f, f')$ and we get bounds for the quotient $m^*/Λ$ with different values of $(f, f')$. We conclude that both asymmetries produce bounds for such quotient when $f'$ overweigth to $f$, and this fact is related with the breakdown of the custodial symmetry.

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BibTeX RIS

R. Diaz, R. Martinez, J. -Alexis Rodriguez. 1998-09-16. Compositeness and the asymmetries of leptons at the Z^0 peak. https://arxiv.org/abs/hep-ph/9710535

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