Phenomenology of flavon fields at the LHC

TL;DR

This paper investigates the phenomenology of flavon fields associated with a non-supersymmetric Abelian family symmetry at the TeV scale, focusing on their production, decay, and constraints from low-energy processes at the LHC.

Contribution

It introduces an effective U(1) symmetry broken explicitly to explore flavon phenomenology, including production mechanisms and decay modes at the LHC, constrained by low-energy flavor violation data.

Findings

Flavons with mass up to ~150 GeV are compatible with current constraints.

Flavons can be produced via gluon fusion and single top channels at the LHC.

Characteristic decay modes include t c̄ and τ μ̄, aiding detection.

Abstract

We study low energy constraints from flavour violating processes, production and decay at the LHC of a scalar field varphi (flavon) associated to the breaking of a non-supersymmetric Abelian family symmetry at the TeV scale. This symmetry is constrained to reproduce fermion masses and mixing, up to O(1) coefficients. The non-supersymmetric gauged U(1) models considered are severely restricted by cancellation of anomalies and LEP bounds on contact interactions, consequently its phenomenology is out of the LHC reach. We therefore introduce an effective U(1) which is not gauged and it is broken explicitly by a CP odd term at the TeV scale. This helps us to explore flavour violating processes, production and decay at the LHC for these kind of light scalars. In this context we first study the constraints on the flavon mass and its vacuum expectation value from low energy flavour changing processes such as \mu -> e\gamma . We find that a flavon of about m_\phi <~ 150 GeV could be experimentally allowed. These kind of flavons could be significantly generated at the LHC via the gluon fusion mechanism and the single top production channel g u -> t \phi. The produced flavons can have characteristic decay modes such as t \bar{c} for m_\phi >~ m_t, and \tau \bar{\mu} for m_\phi <~ m_t, which could be effectively useful to detect flavons.