Cosmological baryon production versus intermediate mass scales?

Abstract

We analyze the conditions for a late cosmological matter-antimatter asymmetry production at some intermediate energy scale ∼106 GeV. We envisage a new class of models where the compatibility between enough βB production and decoupling of subsequent B violating interactions at T ∼ 106GeV is automatically achieved through the assumption of weak coupling between B nonconserving particles and ordinary matter. Possible consequences for nucleon stability are analyzed. The mechanism could be interesting for dynamical schemes (technicolor, composite models) where B production seems very difficult to be obtained before T ∼ ΛH. Furthermore a late origin of matter-antimatter asymmetry could be essential in the resolution of some cosmological puzzles, such as the excess of monopole density.