Q-ball Formation through Affleck-Dine Mechanism

TL;DR

This paper uses numerical simulations to demonstrate how large Q-balls form from the fragmentation of a scalar field condensate via the Affleck-Dine mechanism, with their sizes and charges determined by initial conditions.

Contribution

It provides the first full nonlinear simulation of Q-ball formation through the Affleck-Dine mechanism, linking Q-ball properties to initial charge densities and fluctuation modes.

Findings

Large Q-balls are produced by condensate fragmentation.

Q-ball size is set by the most developed fluctuation mode.

Almost all initial charge is absorbed into Q-balls.

Abstract

We present the full nonlinear calculation of the formation of a Q-ball through the Affleck-Dine (AD) mechanism by numerical simulations. It is shown that large Q-balls are actually produced by the fragmentation of the condensate of a scalar field whose potential is very flat. We find that the typical size of a Q-ball is determined by the most developed mode of linearized fluctuations, and almost all the initial charges which the AD condensate carries are absorbed into the formed Q-balls, whose sizes and the charges depend only on the initial charge densities.