The Sphaleron Rate: Bodeker's Leading Log

Bodeker has recently shown that the high temperature sphaleron rate, which measures baryon number violation in the hot standard model, receives logarithmic corrections to its leading parametric behavior; Gamma = kappa' [log(m_D / g^2 T) + O(1)] (g^2 T^2 / m_D^2) \alpha_W^5 T^4. After discussing the physical origin of these corrections, I compute the leading log coefficient numerically; kappa' = 10.8 pm 0.7. The log is fairly small relative to the O(1) ``correction;'' so nonlogarithmic contributions dominate at realistic values of the coupling.