Cosmic Topological Defects, Highest Energy Cosmic Rays, and the Baryon Asymmetry of the Universe

Abstract

It is pointed out that the observed extremely high energy cosmic rays (EHECR) above ${10}^{11}\mathrm{GeV}$ and the observed baryon asymmetry of the Universe (BAU) may have a common origin in baryon number violating decays of supermassive $X$ particles released from cosmic topological defects (TDs) such as cosmic strings and monopoles. The $X$ particles produced by TDs in the recent epochs produce the EHECR, while the BAU is created by $X$ particles released from TDs mainly in the very early Universe. In this scenario the EHECR is predicted to contain baryons as well as antibaryons with a small asymmetry between the two.