Simulations of Cold Electroweak Baryogenesis: Finding the optimal quench time

Abstract

We revisit the numerical computation of the baryon asymmetry from Cold Electroweak Baryogenesis given the physical Higgs mass. We investigate the dependence of the asymmetry on the speed at which electroweak symmetry breaking takes place. The maximum asymmetry does not occur for arbitrarily fast quenches, but at quench times of about $\tau_q\simeq 16\, m_H^{-1}$, with no asymmetry created for quenches slower than $\tau_q>30\, m_H^{-1}$. Curiously, we also find that the overall sign of the asymmetry depends on the quench time.