B → τν in two-Higgs doublet models with MFV

Abstract

We analyse the B → τν decay in a generic two-Higgs doublet model satisfying the MFV hypothesis. In particular, we analyse under which conditions $$\mathcal{B}(B \to \tau \nu )$$ can be substantially enhanced over its SM value, taking into account the constraints of K → τν, B → X s γ, and B s → μ + μ −. We find that for large tan β values and Peccei-Quinn symmetry breaking terms of $$\mathcal{O}(1/\tan \beta )$$ a sizable (∼ 50%) enhancement of $$\mathcal{B}(B \to \tau \nu )$$ is possible, even for m H ∼ 1 TeV.