Dark matter in the $SO(5)\times U(1)$ gauge-Higgs unification

TL;DR

This paper proposes a gauge-Higgs unification model where the lightest neutral dark fermion naturally accounts for the observed dark matter relic abundance, consistent with experimental constraints, with specific mass predictions.

Contribution

It introduces a specific $SO(5) imes U(1)$ gauge-Higgs unification model with dark fermions that explains dark matter relic abundance and fits experimental bounds.

Findings

Dark fermions can reproduce observed relic abundance.

Lightest dark fermion mass ranges from 2.3 to 3.1 TeV.

Model remains consistent with direct detection constraints.

Abstract

In the $SO(5) \times U(1)$ gauge-Higgs unification the lightest, neutral component of $n_F$ $SO(5)$-spinor fermions (dark fermions), which are relevant for having the observed unstable Higgs boson, becomes the dark matter of the universe. We show that the relic abundance of the dark matter determined by WMAP and Planck data is reproduced, below the bound placed by the direct detection experiment by LUX, by a model with one light and three heavier ($n_F=4$) dark fermions with the lightest one of a mass from 2.3$\,$TeV to 3.1$\,$TeV. The corresponding Aharonov-Bohm phase $\theta_H$ in the fifth dimension ranges from 0.097 to 0.074. The case of $n_F=3$ ($n_F = 5, 6$) dark fermions yields the relic abundance smaller (larger) than the observed limit.