Charge-Swapping Q-balls in a Logarithmic Potential and Affleck-Dine condensate fragmentation

Abstract

We study charge-swapping Q-balls, a kind of composite Q-ball where positive and negative charges co-exist and swap with time, in models with a logarithmic potential that arises naturally in supersymmetric extensions of the Standard Model. We show that charge-swapping Q-balls can be copiously generated in the Affleck-Dine fragmentation process in the early universe. We find that the charge-swapping Q-balls with the logarithmic potential are extremely stable. By performing long time, parallelized lattice simulations with absorbing boundary conditions, we find that the lifetimes of such objects with low multipoles are at least $4.6 \times 10^5/m$ in 3+1D and $2.5 \times 10^7/m$ in 2+1D, where $m$ is the mass scale of the scalar field. We also chart the attractor basin of the initial conditions to form these charge-swapping Q-balls.