Axino dark matter from Q-balls in Affleck-Dine baryogenesis and the ${\Omega }_b-{\Omega }_{DM}$ coincidence problem

Abstract

We show that the ${\Omega }_b-{\Omega }_{DM}$ coincidence can naturally be explained in a framework where axino cold dark matter is predominantly produced in non-thermal processes involving decays of Q-balls formed in Affleck-Dinebaryogenesis. In this approach the similarity between ${\Omega }_b$ and ${\Omega }_{DM}$ is a direct consequence of the (sub-)GeV scale of the mass of the axino.

Comments: 4 pages, no figure, final PRL version