Related papers: Two Higgs Pair Heterotic Vacua and Flavor-Changing…
We analise phenomenological implications of two Higgs doublet models with Higgs flavour changing neutral currents suppressed in the quark sector by small entries of the Cabibbo-Kokayashi-Maskawa matrix. This suppression occurs in a natural…
We {works done in collaboration with C.S.Kim, Yonsei Univ., Seoul, Korea} present some properties of the SM with two Higgs doublets. Unlike the minimal SM, the Yukawa couplings (in the usual ``type II'' model) converge with the increasing…
Two Higgs-doublet models usually consider an ad-hoc $\mathbb{Z}_2$ discrete symmetry to avoid flavor changing neutral currents. We consider a new class of two Higgs-doublet models where $\mathbb{Z}_2$ is enlarged to the symmetry group…
We point out that the stringent lower bounds on the masses of additional electrically neutral and charged Higgs bosons crucially depend on the flavour structure of their Yukawa interactions. We show that these bounds can easily be evaded by…
In multi-Higgs-doublet models, the alignment in flavour space of all Yukawa matrices coupling to a given right-handed fermion guarantees the absence of tree-level flavour-changing neutral couplings, while introducing new sources of CP…
In extended Higgs models, a discrete symmetry is needed in the quark sector to avoid tree-level flavor-changing neutral currents. However, this is not necessary the case in the lepton sector. We consider a model in which one Higgs couples…
The fundamental constraint on two Higgs doublet models comes from the requirement of sufficiently suppressing flavor-changing neutral currents. There are various standard approaches for dealing with this problem, but they all tend to share…
Gauge-Higgs unification is the fascinating scenario solving the hierarchy problem without supersymmetry. In this scenario, the Standard Model (SM) Higgs doublet is identified with extra component of the gauge field in higher dimensions and…
We study flavor violating processes in the production or decay of a neutral pseudoscalar meson $P^0$ in the framework of a general two Higgs Doublet Model type III (2HDM-III). We use a version of the model where Yukawa interactions of…
We consider a 4-Higgs-doublet model in which each Higgs doublet gives mass to one of the fermion sets $\{ m_t\}$, $\{ m_b,m_\tau,m_c \}$, $\{ m_\mu,m_s \}$, and $\{ m_d,m_u,m_e \}$. The sets have the feature that within each of them the…
We investigate the possibility of having sizable effects from flavor changing neutral currents at the tree level in a particular class of Two Higgs Doublet Models. Constraints from existing experimental information are discussed. Some…
We study the charged Higgs couplings to fermions in the "democratic" three-Higgs-doublet model, in which one doublet couples to down-type quarks, one to up-type quarks, and one to charged leptons. Flavor-changing neutral Higgs couplings are…
The simplest extension of the standard model involves adding a scalar doublet--the so-called two-Higgs model. In general, the additional scalar will mediate tree-level flavor-changing neutral currents. Although one can arbitrarily impose a…
We introduce a composite Higgs model in which a flavour deconstructed gauge group is embedded in the strong sector. The pattern of global symmetry breaking yields, as pseudo-Nambu-Goldstone (pNGB) bosons, both a Standard Model (SM)-like…
In this letter we demonstrate a new source for large flavor-changing neutral currents within the minimal supersymmetric standard model. At moderate to large tan(beta), it is no longer possible to diagonalize the masses of the quarks in the…
We construct extensions of the Standard Model with two Higgs doublets, where there are flavour changing neutral currents both in the quark and leptonic sectors, with their strength fixed by the fermion mixing matrices $V_{CKM}$ and…
We demonstrate that flavour-changing neutral currents in the top sector, mediated by leptophilic scalars at the electroweak scale, can easily arise in scenarios of new physics, and in particular in composite Higgs models. We moreover show…
We propose a Three Higgs Doublet Model (3HDM) that goes beyond natural flavor conservation and in which each of the three Higgs doublets couples mainly to a single generation of fermions via non-standard Yukawa structures. A hierarchy in…
We discuss the possibility that flavor hierarchies arise from the electroweak scale in a two Higgs doublet model, in which the two Higgs doublets jointly act as the flavon. Quark masses and mixing angles are explained by effective Yukawa…
Flavour changing neutral current processes, being strongly suppressed in the Standard Model (SM), provide a unique window to new physics at scales much above the electroweak scale. Here, we summarize the recent progress in flavour physics…