Low-energy effects of Charged Higgs with general Yukawa couplings

We study a model with two Higgs doublets where FCNC are allowed at tree-level. In this model, the interactions of charged Higgs with fermions ($H^\pm f \bar{f'}$), include a term that is not proportional to the fermion masses, which we constraint using the following low-energy processes: i) tau decays ($\tau \to \nu_{\tau} e\nu_e, \nu_{\tau}\mu\nu_{\mu}, \nu_{\tau}\pi$), ii) leptonic decays of pseudoscalar mesons ($\pi, K \to \ell\nu_{\ell}$) and iii) semileptonic b-decays. With these constraints it is possible to make predictions; we illustrate this by presenting the rates for the (FCNC) decay $c\to u+\gamma$, the (second class-current) decay $\tau\to \nu_{\tau}+ \eta\pi$, and also the theoretical value of the neutron life-time.