Related papers: Two-loop corrections to the $\rho$ parameter in Tw…
One of the most straightforward extensions of the standard model (SM) is having an additional Higgs doublet to the SM, namely the two Higgs doublet models(THDM). In the type-I model, an additional Higgs doublet is introduced that does not…
Precision predictions play an important role in the search for indirect New Physics effects in the Higgs sector itself. For the electroweak (EW) corrections of the Higgs bosons in extended Higgs sectors several renormalization schemes have…
I present the leading 3-loop contributions to the Fermi decay constant in the Standard Model, using the tadpole-free pure $\overline{\rm{MS}}$ scheme. The calculation is exact in the limit in which the QCD coupling, the top-quark Yukawa…
We present detailed results of a diagrammatic calculation of the leading two-loop QCD corrections to the masses of the neutral CP-even Higgs bosons in the Minimal Supersymmetric Standard Model (MSSM). The two-loop corrections are…
Recent results for the leading $\mathcal{O}{\left(\alpha_t^2\right)}$ two-loop corrections to the Higgs-boson masses of the MSSM with complex parameters are presented. The strategy of the Feynman-diagrammatic, analytical calculation is…
Theoretical uncertainties affecting electroweak observables are reviewed and the relevance of two-loop electroweak radiative corrections for the precision tests of the Standard Model is discussed.
We present an analytical calculation of the leading three-loop radiative correction to the rho-parameter in the Standard Model in the large Higgs mass limit. This correction, of order g^6 m_H^4/M_W^4, is opposite in sign to the leading…
The Higgs-mass dependence of the Standard Model contributions to the correlation between the gauge-boson masses is studied at the two-loop level. Exact results are given for the Higgs-dependent two-loop corrections associated with the…
The Two-Higgs Doublet Model (2HDM) is one of the most popular and natural extensions of the Higgs sector; but it has two potential fine-tuning problems, related to the electroweak (EW) breaking and the requirement of alignment with the SM…
The Higgs sectors of supersymmetric extensions of the Standard Model have two doublets in the minimal version (MSSM), and two doublets plus a singlet in two others: with (UMSSM) and without (NMSSM) an extra U(1)'. A very concise comparison…
We update the phenomenology of gauge singlet extensions of the Standard Model scalar sector and their implications for the electroweak phase transition. Considering the introduction of one real scalar singlet to the scalar potential, we…
The complete set of Higgs-boson two-loop contributions to electric dipole moments of the electron and neutron is calculated in the minimal supersymmetric standard model. The electric dipole moments are induced by CP-violating trilinear…
We calculate Higgs coupling constants at one-loop level in the Higgs triplet model (HTM) to compare to future collider experiments. We evaluate the decay rate of the standard model (SM)-like Higgs boson ($h$) into diphoton. Renormalized…
We present a precise analysis of the Higgs mass corrections stemming from vectorlike top partners in supersymmetric models. We reduce the theoretical uncertainty compared to previous studies in the following aspects: (i) including the…
I present a method for accurately calculating the pole mass of the lightest Higgs scalar boson in supersymmetric extensions of the Standard Model, using a mass-independent renormalization scheme. The Higgs scalar self-energies are…
The one-loop contributions to the branching ratios for leptonic tau decays are calculated in the CP conserving 2HDM(II). We found that these one-loop contributions, involving both neutral and charged Higgs bosons, dominate over the…
I present results for the two-loop self-energy functions for neutral and charged Higgs scalar bosons in minimal supersymmetry. The contributions given here include all terms involving the QCD coupling, and those following from Feynman…
In most of the mass range encompassed by the limits from the direct search and the electroweak precision tests, the Higgs boson of the standard model preferably decays to bottom quarks. We present, in analytic form, the dominant two-loop…
The electroweak corrections of order ${\cal O}(\alpha_{\rm em} m^2_{t,b}/m^2_w)$ and ${\cal O}(\alpha_{\rm em} m^3_{t,b}/m^3_w)$ to Higgs boson associated production with top quark pair are calculated at $e^+e^-$ colliders in the standard…
In the standard model (SM) of electroweak interactions, CP noninvariance arises from the nonzero phase in the CKM matrix. Its contribution to the quark electric dipole moment (EDM) vanishes surprisingly at two loop order. This makes the…