Supersymmetric electroweak baryogenesis

We calculate the baryon asymmetry generated at the electroweak phase transi tion in the minimal supersymmetric standard model, using a new approach to compute the CP-violating asymmetry in the Higgsino flux reflected into the unbroken phase. The approach is based on a Higgs insertion expansion. We fi nd that the CP asymmetry at leading order is proportional to the change in Delta beta in the bubble wall, which is at most of order 10(-2), while at n ext-to-leading order this suppression factor disappears. These results expl ain part of the previous discrepancies among different calculations and may enhance the final baryon asymmetry generated during the electroweak phase transition.