Numerical study of Q-ball formation in gravity mediation

TL;DR

This paper uses numerical simulations to analyze Q-ball formation in an expanding universe, revealing a higher peak charge distribution than previously known and discussing the formation process and deviations from past conjectures.

Contribution

It provides detailed lattice simulation results of Q-ball formation across dimensions, showing a higher peak charge distribution and insights into formation dynamics.

Findings

Q-ball charge distribution peaks at Q^{3D}_{peak}  1.9^{-2} (|\u03a6_{in}|/m)^2

The peak charge is about 60% greater than previous estimates

Discussion on the formation process and deviations from past conjectures

Abstract

We study Q-ball formation in the expanding universe on 1D, 2D and 3D lattice simulations. We obtain detailed Q-ball charge distributions, and find that the distribution is peaked at Q^{3D}_{peak} \simeq 1.9\times 10^{-2} (|\Phi_{in}|/m)^2, which is greater than the existing result by about 60%. Based on the numerical simulations, we discuss how the Q-ball formation proceeds. Also we make a comment on possible deviation of the charge distributions from what was conjectured in the past.