Effective theories and resonances in strongly-coupled electroweak symmetry breaking scenarios

TL;DR

This paper explores the use of effective field theories with resonances to understand strongly-coupled electroweak symmetry breaking, emphasizing how high-energy resonances influence low-energy observables.

Contribution

It develops a comprehensive framework connecting high-energy resonances with low-energy effective theories in non-linear electroweak symmetry breaking scenarios.

Findings

Resonance imprints can be observed in low-energy constants.

Effective Lagrangian formulations for both low and high energies.

Phenomenological links between resonances and experimental signatures.

Abstract

Due to the mass gap between the Standard Model and possible New Physics states, electroweak effective approaches are appropriate. Although a linear realization of the electroweak symmetry breaking with the Higgs forming a doublet together with the Goldstone bosons of the EWSB is a first possibility (SMEFT), we adopt the more general non-linear realization, where the Higgs is a singlet with independent couplings (EWET, HEFT or EWChL). We present the effective Lagrangian at low energies (the EWET, with only the SM fields) and at high energies (the resonance theory, with also a set of resonances). Taking into account the high scale of these resonances, their experimental searches seem to be more accessible by considering their imprints at low-energies, i.e., their imprints in the Low Energy Constants (LECs) of the EWET at energies lower than the resonance masses. We give some examples of these phenomenological connections.