Related papers: Electroweak Corrections to $B_{s,d} \to \ell^+ \el…
We study the scheme dependence of the two-loop expression for the $\rho$-parameter of the Standard Model in the heavy $t$-quark mass limit $m_{t} \gg m_{w}$. In the $\ms$-scheme the two-loop electroweak correction to the ${\cal…
In a recently proposed extension of the Standard Model with a compact extra dimension of size R we compute the leading corrections, of relative order (m_t R)^2, to the Branching Ratio B -> X_s gamma. For 1/R = 370 \pm 80 GeV, the branching…
We present complete one-loop radiative corrections to the decay rate of a top quark into a charged Higgs boson and a bottom quark, and for the decay of a charged Higgs boson into leptons. The results are discussed in the framework of the…
Full one-loop electroweak corrections to the on-shell decay $H^+ \to W^+A^0$ are computed in the framework of models with two Higgs doublets (THDM). Such a decay may be dominant for $H^{\pm}$ over a wide range of parameter space relevant at…
We calculate the leading-logarithmic and next-to-leading-logarithmic electroweak corrections to the charm-top-quark contribution to the effective $|\Delta S| = 2$ Lagrangian, relevant for the parameter $\epsilon_K$. We find that these…
We present recent results of the rare semileptonic decay B -> X_s l+ l-. We particularly focus on higher order electroweak corrections in the Standard Model (SM) as well as O(alpha_s) corrections in Two-Higgs-doublet models (THDM), both of…
To match the expected experimental precision at future linear colliders, improved theoretical predictions beyond next-to-leading order are required. At the anticipated energy scale of sqrt(s)=1 TeV the electroweak virtual corrections are…
We present the complete electroweak one-loop corrections to the partial widths for two-body decays of a chargino (neutralino) into a W-boson and a neutralino (chargino). We perform the calculation for the minimal and the next-to-minimal…
We have calculated the one-loop electroweak corrections to the decay t-> bW+, including the counterterm for the CKM matrix elements V(tb). Previous calculations used an incorrect delta V(tb) that led to a gauge dependent amplitude. However,…
In this work we give a detailed description of a method for the calculation of QCD corrections to electroweak processes in dimensional regularization that does not require any definition of the gamma_5 matrix in d dimensions. This method…
For the first time the next-to-leading-order electroweak corrections to the full off-shell production of two top quarks that decay leptonically are presented. This calculation includes all off-shell, non-resonant, and interference effects…
We have examined the evidence for the electroweak radiative corrections in the LEP precision data along with the intriguing possibility that the QED corrections only may be sufficient to fit the data. We find that the situation is very…
Within the framework of the MSSM, we compute the electroweak one-loop supersymmetric quantum corrections to the width $\Gamma (t\rightarrow W^{+}\, b)$ of the canonical main decay of the top quark. The results are presented in two on-shell…
We study electroweak parameters sensitive to the radiative corrections, such as $\rho$-ratio and $\hff$ decay rates in the $\ms$-scheme in the heavy $t$-quark mass limit $m_{t} \gg m_{w}$. In $\ms$-scheme the two-loop electroweak…
We present the electroweak one-loop corrections to the processes e+e- -> f bar-f, f = tau, c, b, t, at energies relevant for a future linear collider. The results of two independent calculations are compared and agreement is found at a…
We compute the dominant logarithmically enhanced two-loop electroweak corrections to the electron-positron scattering differential cross section in the high energy limit for large scattering angles. Depending on the scattering angle and…
In the supersymmetric extension of the Standard Model we derive the two-loop QCD corrections to the scalar quark contributions to the electroweak precision observables entering via the rho parameter. A very compact expression is derived for…
We discuss the renormalization of the electric charge at the two-loop level in the Standard Model of the electroweak interactions. We explicitly calculate the expression of the complete on-shell two-loop counterterm using the Background…
The cross-section for $\gamma\gamma\to W^+ W^-$ with arbitrary polarized photons and W bosons is calculated within the electroweak Standard Model including the complete virtual and soft-photonic ${\cal O}(\alpha)$ corrections. We present a…
The cross-section for W^+W^- \to W^+W^- with arbitrarily polarized W bosons is calculated within the Electroweak Standard Model including the complete virtual and soft-photonic O(alpha) corrections. We show the numerical importance of the…