New charged Higgs effects on ${\Gamma }_{K_{e2}}/{\Gamma }_{K_{\mu 2}}$, $f_{D_s}$ and $\mathcal{B}(B^{+}\to {\tau }^{+}\nu )$ in the Two-Higgs-Doublet model

Abstract

A new scheme for Yukawa matrices is proposed for free of flavor changing neutral currents (FCNCs) at tree level in general two-Higgs-doublet model (THDM) without imposing symmetry. We find that the new type couplings of charged Higgs to fermions not only depend on the flavors, but also can be ascribed by new CP violating phases. Unlike conventional THDM, the resulted new charged Higgs effects could have the specialties: (a) the influence on $\Gamma (K_{e2}^{\pm })/\Gamma (K_{\mu 2}^{\pm })$ cannot be eliminated, (b) the decay constant of $D_s$ could be enhanced, and (c) enhancement of branching ratio for $B^{+}\to {\tau }^{+}\nu$ could be achieved.

Comments: 13 pages, 5 figures, references added, typos corrected, constraints from R_\pi and B\to D \tau \bar \nu included, final version to appear in PLB