Constraints on a General Higgs Sector from $K^0-\bar K^0$, $B_d- \bar B_d$ Mixing and the $\epsilon$ Parameter

Abstract

The scalar sector of the Standard Model is extended to include an arbitrary assortment of scalars. In the case where this assignment does not preserve $\rho=1$ at the tree-level, the departure from unity itself puts the most stringent constraint on the scalar sector, and where $\rho_{tree}=1$ is maintained, useful bounds on the parameter space of the charged Higgs mass and the doublet-nondoublet mixing angle can arise from data on $\bbbar$, $\kkbar$ mixing and the $\e$ parameter. These constraints turn out to be comparable (and in some cases, better) to those obtained from $\zbb$ data.