Gauged Q ball in a piecewise parabolic potential

TL;DR

This paper analyzes gauged Q ball solutions in a complex scalar field theory with a parabolic potential, revealing size limitations due to Coulomb repulsion and providing an analytic expression beyond the thin-walled approximation.

Contribution

It introduces an explicit maximum size for gauged Q balls caused by Coulomb forces and derives an analytic solution beyond the thin-walled limit.

Findings

Maximum size of gauged Q balls due to Coulomb repulsion

Size increases as the potential's local minimum decreases

Analytic expression for gauged Q balls beyond thin-walled limit

Abstract

Q ball solutions are considered within the theory of a complex scalar field with a gauged U(1) symmetry and a parabolic-type potential. In the thin-walled limit, we show explicitly that there is a maximum size for these objects because of the repulsive Coulomb force. The size of Q ball will increase with the decrease of local minimum of the potential. And when the two minima degenerate, the energy stored within the surface of the Q ball becomes significant. Furthermore, we find an analytic expression for gauged Q ball, which is beyond the conventional thin-walled limit.