Gauged Q-balls in flat potentials

TL;DR

This paper investigates gauged Q-balls in flat potentials, providing analytic approximations and numerical comparisons, and explores the impact of massive gauge bosons on these solitons.

Contribution

It extends the study of gauged Q-balls to flat potentials, often found in supersymmetric models, and analyzes the effects of gauge boson mass on their properties.

Findings

Gauged Q-balls in flat potentials are similar to those in Coleman's models.

Analytic approximations match well with numerical solutions.

Massive gauge bosons interpolate between global and gauged Q-balls.

Abstract

Q-balls are large bound-state systems of scalar particles, described classically through localized solutions of the equations of motion. Promoting the required stabilizing $U(1)$ symmetry to a gauge symmetry leads to gauged Q-balls, which cannot grow beyond some maximal size and charge on account of the repulsive gauge interactions. These gauged Q-balls have been studied extensively for scalar potentials that satisfy Coleman's thin-wall criterion; here, we explore gauged Q-balls in flat potentials, which often occur in supersymmetric models. Even though global Q-balls in flat potentials are qualitatively different from Coleman's Q-balls, we find that the gauged versions are remarkably similar. We provide analytic approximations for these solitons and compare to numerical solutions. In addition, we study Proca Q-balls, i.e. make the gauge bosons massive, which interpolates between the global and gauged cases.