The classical sphaleron transition rate exists and is equal to $1.1({\alpha }_{w}T{)}^4$

Abstract

Results of a large scale numerical simulation show that the high temperature Chern-Simons number diffusion rate in the electroweak theory has a classical limit $\Gamma =\kappa ({\alpha }_{w}T{)}^4$, where $\kappa =1.09\pm 0.04$ and ${\alpha }_w$ is the weak fine structure constant.

Comments: 12 pages, plain LaTeX, figures part of the LaTeX source, minor errors corrected, acknowledgment added, to be published in Phys. Lett. B