Fermion Delocalization in Higgsless Models

S. De Curtis

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arXiv · hep-ph/0512158

Fermion Delocalization in Higgsless Models

S. De Curtis

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Abstract

In the linear moose framework, which naturally emerges in deconstruction models, we discuss the effect of direct couplings between the left-handed fermions living on the boundary of the chain and the gauge fields in the internal sites. This is realized by means of a product of nonlinear sigma-model scalar fields which, in the continuum limit, is equivalent to a Wilson line. The effect of these new nonlocal couplings is a contribution to the S parameter which can be of opposite sign with respect to the one coming from the gauge fields along the string. Therefore, with some fine-tuning, it is possible to satisfy the constraints from the electro-weak data without spoiling the perturbative unitarity limit, which, in these models is generally postponed with respect to the Higgsless Standard Model one.

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S. De Curtis. 2005-12-13. Fermion Delocalization in Higgsless Models. https://arxiv.org/abs/hep-ph/0512158

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