Magnetic monopoles as probes of the global structure of the Standard Model

TL;DR

This paper explores how the global structure of the Standard Model's gauge group constrains magnetic monopoles, identifying surviving monopoles after symmetry breaking and analyzing their properties and detectability.

Contribution

It reveals the selection rules for monopoles based on gauge group structure and magnetic symmetries, and studies their propagation and suppression mechanisms.

Findings

Certain monopoles with specific magnetic charges can survive as isolated states.

Relic abundance of these monopoles can be suppressed by symmetry breaking scale.

Monopoles with Lorentz factor up to 10^4 have ionisation profiles scaling as g^2.

Abstract

The magnetic charges of monopoles arising in ultraviolet completions of the Standard Model are constrained by the global structure of the gauge group. After electroweak symmetry breaking, a subset of the ultraviolet monopoles carrying magnetic charges 3$g_D$ and $6g_D$ can survive as isolated, colour-neutral states in the infrared. We show that this selection rule follows from the interplay between the symmetry structure and the magnetic 1-form symmetry, and discuss how the relic abundance of such monopoles can be naturally suppressed by the symmetry breaking scale. We further demonstrate that such monopoles with Lorentz factor $\gamma\lesssim 10^4$ propagate through matter with ionisation energy loss profiles scaling as $g^2$ using CORSIKA Monte Carlo simulations.