Related papers: The flavor puzzle in multi-Higgs models
We study the deviation of yukawa coupling in the gauge-Higgs unification scenario from the Standard Model one. Taking into account the brane mass terms necessary for generating the flavor mixing and removing the exotic massless fermions, we…
If one removes any \emph{ad hoc} symmetry assumptions, the general two Higgs doublet model should have additional Yukawa interactions independent from fermion mass generation, in general involving flavor changing neutral Higgs couplings.…
In models with non-minimal Higgs sectors, enforcing (near) Higgs alignment, necessary to prevent significant deviations in the Higgs boson coupling from the standard model prediction, causes a serious fine-tuning problem. We demonstrate…
CP4 3HDM is a peculiar three-Higgs-doublet model in which a single symmetry leads to tight constraints on the scalar and Yukawa sectors. In this models, tree-level flavor-changing neutral couplings are unavoidable; however, as previously…
In this paper, we study the CP violating processes in a general two-Higgs-doublet model (2HDM) with tree-level flavor changing neutral currents. In this model, sizable Yukawa couplings involving top and charm quarks are still allowed by the…
We study Two-Higgs-Doublet Models (2HDM) where Abelian symmetries have been introduced, leading to a drastic reduction in the number of free parameters in the 2HDM. Our analysis is inspired in BGL models, where, as the result of a symmetry…
Due to the smallness of the lepton Yukawa couplings, higher-dimensional operators can give a significant contribution to the lepton masses. In this case, the lepton mass matrix and the matrix of lepton-Higgs couplings are misaligned leading…
We consider two Higgs doublet models (THDMs) with both the Higgs potential and Yukawa interactions being aligned, which we call "double-aligned THDMs". In this scenario, coupling constants of the discovered Higgs boson to the Standard Model…
The triviality of the scalar sector of the standard one-doublet Higgs model implies that this model is only an effective low-energy theory valid below some cut-off scale $\Lambda$. The underlying high-energy theory must include flavor…
We consider composite two-Higgs doublet models based on gauge-Yukawa theories with strongly interacting fermions generating the top-bottom mass hierarchy. The model features a single "universal" Higgs-Yukawa coupling, $ g $, which is…
Yukawa couplings of the first quark generation are notoriously difficult to constrain due to their small values within the Standard Model. Here we propose Higgs off-shell production, with the Higgs boson decaying to four leptons, as a probe…
We present a non-trivial correlation between the enhancement of the Higgs-fermion couplings and the Higgs pair production cross section in two Higgs doublet models with a flavour symmetry. This symmetry suppresses flavour-changing neutral…
We analyze flavor constraints in the littlest Higgs model with T-parity. In particular, we focus on neutral meson mixing in the K, B, and D systems due to one loop contributions from T-parity odd fermions and gauge bosons. We calculate the…
In this paper, we introduce Unitary Flavour Violation to produce Multi-Higgs Doublets Models where all flavour parameters are contained within three unitary matrices. After that, we identify two of its subclasses, the left and right models,…
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…
The spontaneous breaking of the $SU(3)^5$ quark/lepton flavor symmetry by means of three multiplets of scalar `Yukawa fields' admits vacua with one O(1) and two vanishing vacuum expectation values (vevs) for each multiplet. If the number of…
We consider multi-Higgs-doublet models which, for symmetry reasons, have a universal Higgs-Yukawa (HY) coupling, $g$. This is identified with the top quark $g=g_t\approx 1$. The models are concordant with the quasi-infrared fixed point, and…
We study the LHC phenomenology of flavor changing Yukawa couplings between top quark, Higgs boson, and either an up or charm quark. Such $tuh$ or $tch$ couplings arise for instance in models in which Higgs sector is extended by the…
We construct a three-Higgs doublet model with a flavour non-universal ${\rm U}(1)\times \mathbb{Z}_2$ symmetry. That symmetry induces suppressed flavour-changing interactions mediated by neutral scalars. New scalars with masses below the…
We assume that weak bases of flavors (u, c)_{L,R}, (d,s)_{L,R}, (e, \mu) _{L,R}, (\nu_e, \nu_\mu)_{L,R} are the S_3 doublet and t_{L,R}, b_{L,R}, \tau_{L,R}, {\nu_\tau}_{L,R} are the S_3 singlet and further there are S_3 doublet Higgs…