Q-balls without a potential

TL;DR

This paper investigates non-topological Q-ball solutions in a two-component model, revealing the existence and stability of hairy Q-balls without a potential and exploring spinning axially symmetric solutions.

Contribution

It introduces the concept of hairy Q-balls with massless fields and demonstrates their stability and existence in a potential-free limit.

Findings

Hairy Q-balls exist without a scalar potential.

Spinning axially symmetric Q-balls are numerically confirmed.

Hairy Q-balls are classically stable across all angular frequencies.

Abstract

We study non-topological Q-ball solutions of the (3+1)-dimensional Friedberg-Lee-Sirlin two-component model. The limiting case of vanishing potential term yields an example of hairy Q-balls, which possess a long range massless real field. We discuss the properties of these stationary field configurations and determine their domain of existence. Considering Friedberg-Lee-Sirlin model we present numerical evidence for the existence of spinning axially symmetric Q-balls with different parity. Solution of this type exist also in the limiting case of vanishing scalar potential. We find that the hairy Q-balls are classically stable for all range of values of angular frequency.