Testing the Nambu-Goldstone Hypothesis for Quarks and Leptons at the LHC

TL;DR

This paper proposes a model where certain fermions are pseudo-Nambu-Goldstone bosons, explaining their small masses, and demonstrates how these models can be tested at the LHC through distinctive signatures.

Contribution

It introduces a novel class of models linking fermion masses to pseudo-Nambu-Goldstone bosons and shows their testability at the LHC with specific experimental signatures.

Findings

Model regions can produce correct dark matter abundance.

Regions evade other phenomenological constraints.

Distinctive LHC signatures include fewer b- and tau-jets and many multi-lepton events.

Abstract

The hierarchy of the Yukawa couplings is an outstanding problem of the standard model. We present a class of models in which the first and second generation fermions are SUSY partners of pseudo-Nambu-Goldstone bosons that parameterize a non-compact Kahler manifold, explaining the small values of these fermion masses relative to those of the third generation. We also provide an example of such a model. We find that various regions of the parameter space in this scenario can give the correct dark matter abundance, and that nearly all of these regions evade other phenomenological constraints. We show that for gluino mass ~700 GeV, model points from these regions can be easily distinguished from other mSUGRA points at the LHC with only 7 fb^(-1) of integrated luminosity at 14 TeV. The most striking signatures are a dearth of b- and tau-jets, a great number of multi-lepton events, and either an "inverted" slepton mass hierarchy, narrowed slepton mass hierarchy, or characteristic small-mu spectrum.