Affleck-Dine Cogenesis

TL;DR

This paper introduces a new framework where baryon and dark matter abundances are generated simultaneously through the Affleck-Dine mechanism, linking their origins and explaining their observed ratio.

Contribution

It presents a novel Affleck-Dine cogenesis model that connects baryon and dark matter asymmetries via a single superpotential operator, with implications for dark matter stability and particle lifetimes.

Findings

Achieves the observed dark matter to baryon density ratio of about 5.

Predicts macroscopic lifetimes for the lightest observable supersymmetric particles.

Provides a mechanism for asymmetric dark matter generation linked to baryogenesis.

Abstract

We propose a novel framework in which the observed baryon and dark matter abundances are simultaneously generated via the Affleck-Dine mechanism. In its simplest realization, Affleck-Dine cogenesis is accomplished by a single superpotential operator and its A-term counterpart. These operators explicitly break B-L and X, the dark matter number, to the diagonal B-L+X. In the early universe these operators stabilize supersymmetric flat directions carrying non-zero B-L and X, and impart the requisite CP violation for asymmetry generation. Because B-L+X is preserved, the resulting B-L and X asymmetries are equal and opposite, though this precise relation may be relaxed if B-L and X are violated separately by additional operators. Our dark matter candidate is stabilized by R-parity and acquires an asymmetric abundance due to its non-zero X number. For a dark matter mass of order a few GeV, one naturally obtains the observed ratio of energy densities today, Omega_{DM}/Omega_B \sim 5. These theories typically predict macroscopic lifetimes for the lightest observable supersymmetric particle as it decays to the dark matter.