No Arabic abstract
We discuss the formulation of the general two-Higgs doublet model type III, which incorporates flavor changing neutral scalar interactions (FCNSI) and CP violation from several sources. CP violation can arise either from Yukawa terms or from the Higgs potential, and it can explicit or spontaneous. We discuss the case that includes CP violation with Yukawa textures to control FCNSI and evaluate the CP asymmetry for the decay h-> c-b+ W-, which may allow to test the patterns of FCNSI and CP violation, that arises in these models.
Using the general factorization approach, we present a detailed investigation for the branching ratios, CP asymmetries and longitudinal polarization fractions in all charmless hadronic $B to VV$ decays (except for the pure annihilation processes) within the most general two-Higgs-doublet model with spontaneous CP violation. It is seen that such a new physics model only has very small contributions to the branching ratios and longitudinal polarization fractions. However, as the model has rich CP-violating sources, it can lead to significant effects on the CP asymmetries, especially on those of penguin-dominated decay modes, which provides good signals for probing new physics beyond the SM in the future B-physics experiments.
We carry out a detailed analysis of the general two Higgs doublet model with CP violation. We describe two different parametrizations of this model, and then study the Higgs boson masses and the trilinear Higgs couplings for these two parametrizations. Within a rather general model, we find that the trilinear Higgs couplings have a significant dependence on the details of the model, even when the lightest Higgs boson mass is taken to be a fixed parameter. We include radiative corrections in the one-loop effective potential approximation in our analysis of the Higgs boson masses and the Higgs trilinear couplings. The one-loop corrections to the trilinear couplings of the two Higgs doublet model also depend significantly on the details of the model, and can be rather large. We study quantitatively the trilinear Higgs couplings, and show that these couplings are typically several times larger than the corresponding Standard Model trilinear Higgs coupling in some regions of the parameter space. We also briefly discuss the decoupling limit of the two Higgs doublet model.
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 collider and flavor experiments, while the other couplings are strongly constrained experimentally. The sizable couplings, in general, have imaginary parts and could largely contribute to the CP violating observables concerned with the $B$ and $K$ mesons. In particular, the contribution may be so large that it affects the direct CP violating $K$ meson decay, where the discrepancy between the experimental result and the Standard Model prediction is reported. We discuss how well the anomaly is resolved in the 2HDM, based on study of the other flavor observables. We also propose the way to test our 2HDM at the LHC.
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 TeV scale can still successfully negotiate the constraints arising from flavour data. Such a model can thus encourage direct searches for extra Higgs bosons in the future collider experiments, and includes a non-trivial flavour structure.
We study the effects of CP violation in charged Higgs boson production $ppto t H^pm + X$ at the LHC, as well as in the charged Higgs boson decays $H^pm to t b$ and $H^pm to W^pm H_i^0$, $i=1,2,3$. The study is done in the framework of the type II complex Two Higgs Doublet Model (2HDM) with softly broken $Z_2$ symmetry. In this model violation of CP invariance is induced by the complex parameter $m^2_{12}$ of the tree-level Higgs potential. We calculate the CP violating rate asymmetries for $H^+$ and $H^-$ production and decays as well as for the combined processes at one-loop level and perform a detailed numerical analysis. All calculations are done with the automatic amplitude generator FeynArts and the calculational tool FormCalc, for which we have written a complete complex 2HDM model file and relevant fortran drivers. The implementation of the complex 2HDM in FeynArts and FormCalc is described. In comparison with the analogous results in the MSSM, all considered CP violating asymmetries are smaller by an order of magnitude and do not exceed 2 to 3%.