Baryogenesis and late-decaying moduli

Abstract

Late-decaying string moduli dilute the baryon asymmetry of the Universe created in any previous era. The reheat temperature for such moduli is below a GeV, thus motivating baryogenesis at very low temperatures. We present an extension of the minimal supersymmetric standard model with TeV-scale colored fields that can yield the correct baryon asymmetry of the Universe in this context. Modulus decay, which reheats the Universe at a temperature below GeV, produces the visible sector fields and neutralino dark matter in nonthermal fashion. We discuss various possibilities for baryogenesis from TeV-scale colored fields and show that they can generate an acceptable baryon asymmetry, while being compatible with phenomenological constraints like neutron-antineutron oscillation.