The sphaleron at finite mixing angle

Abstract

The exact sphaleron solution in the bosonic sector of the electro-weak standard model is only known for weak mixing angle θ _w =0. To investigate the behaviour closer to the experimental value θ ^exp _W ≈30° we construct a non-contractible loop in configuration space that is sensitive to θ _W . Our numerical results for the energy and the magnetic dipole moment, combined with previous perturbative results, indicate that the dependence on θ _W is weak.