We calculate the baryon asymmetry of the Universe which would arise during a first-order electroweak phase transition due to minimal-standard-model processes. It agrees in sign and magnitude with the observed baryonic excess, for reasonable Kobayashi-Maskawa parameters and ${\mathit{m}}_{\mathit{t}}$ in the expected range, and plausible values of bubble velocity and other high temperature effects.

• Received 23 November 1992

DOI:https://doi.org/10.1103/PhysRevLett.70.2833