Experimental Constraints on Heavy Fermions in Higgsless Models

TL;DR

This paper investigates constraints on heavy fermions in Higgsless models using an effective Lagrangian approach, focusing on flavor-changing processes to derive bounds applicable to various models with fermion mixing.

Contribution

It introduces a generic analysis framework for heavy fermions in Higgsless models and derives bounds based on flavor-changing neutral current constraints.

Findings

Bounds on heavy fermion parameters derived from FCNC processes

Constraints applicable to a wide class of Higgsless models

Effective Lagrangian approach validated for model-independent analysis

Abstract

Using an effective Lagrangian approach we analyze a generic Higgsless model with composite heavy fermions, transforming as SU(2)_{L+R} Doublets. Assuming that the Standard Model fermions acquire mass through mixing with the new heavy fermions, we constrain the free parameters of the effective Lagrangian studying Flavour Changing Neutral Current processes. In so doing we obtain bounds that can be applied to a wide range of models characterized by the same fermion mixing hypothesis.