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arXiv · 2009.08462

Understanding Q-Balls Beyond the Thin-Wall Limit

Julian Heeck·Arvind Rajaraman·Rebecca Riley·Christopher B. Verhaaren
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Abstract

Complex scalar fields charged under a global U(1) symmetry can admit non-topological soliton configurations called Q-balls which are stable against decay into individual particles or smaller Q-balls. These Q-balls are interesting objects within quantum field theory, but are also of phenomenological interest in several cosmological and astrophysical contexts. The Q-ball profiles are determined by a nonlinear differential equation, and so generally require solution by numerical methods. In this work, we derive analytical approximations for the Q-ball profile in a polynomial potential and obtain simple expressions for the important Q-ball properties of charge, energy, and radius. These results improve significantly on the often-used thin-wall approximation and make it possible to describe Q-balls to excellent precision without having to solve the underlying differential equation.

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Julian Heeck, Arvind Rajaraman, Rebecca Riley, Christopher B. Verhaaren. 2020-09-17. Understanding Q-Balls Beyond the Thin-Wall Limit. https://doi.org/10.1103/physrevd.103.045008

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