Related papers: Supersymmetric contributions to electroweak precis…
Corrections of $O(\alpha_s^2)$ to the decay of the top quark into a W boson and a bottom quark are calculated. The method is based on an expansion of the top quark propagator for small external momentum, q, as compared to the top quark…
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…
We compute the one-loop supersymmetric (SUSY) contributions to the weak charges of the electron ($Q_W^e$), proton ($Q_W^p$), and cesium nucleus ($Q_W^{\rm Cs}$) in the Minimal Supersymmetric Standard Model (MSSM). Such contributions can…
We compute analytically the complete electroweak two-loop corrections to the $B^0-{\bar B}^0$ mixing. These corrections fix the normalization of the electroweak coupling employed in the extraction of $|V_{td}|$ and reduce the theoretical…
QCD corrections to the electroweak one-loop result for the partial width $\Gamma(H\rightarrow b\bar{b})$ are studied. For the decay channel into bottom quarks the rate is affected by a virtual top quark through electroweak interactions. The…
We present the prediction of the electroweak $\rho$ parameter and the $W$ boson mass in the CP-violating Next-to-Minimal Supersymmetric extension of the Standard Model (NMSSM) at the two-loop order. The $\rho$ parameter is calculated at the…
We present virtual contributions up to two loop level in perturbative Quantum Chromodynamic (QCD) to the decay of pseudo-scalar Higgs boson ($A$) to three gluons ($g$) and also to quark ($q$), anti-quark ($\overline q$) and a gluon. With…
In this paper the complete two-loop corrections to the Higgs-boson decay, H -> gamma gamma, are presented. The evaluations of both QCD and electroweak corrections are based on a numerical approach. The results cover all kinematical regions,…
We calculate the $O(\alpha_{ew}m_{t(b)}^{2}/m_{W}^{2})$ and $O(\alpha_{ew} m_{t(b)}^4/m_W^4)$ supersymmetric electroweak corrections to the process $H^+\to W^+h$ in the Minimal Supersymmetric Model. These corrections arise from the virtual…
We calculate the full two-loop electroweak matching corrections to the operator governing the decay B_q --> l^+ l^- in the Standard Model. Their inclusion removes an electroweak scheme and scale uncertainty of about 7% of the branching…
We present an estimate of the next-to-leading order QCD corrections to mixed QCD-electroweak contribution to Higgs boson production cross section in gluon fusion, combining the recently computed three-loop virtual corrections and the…
We present the full ${{\cal O}}(\alpha)$ electroweak radiative corrections to associated Higgs top pair production in $e^+e^-$ collisions. We combine these results with a new calculation of the full one-loop QCD corrections. The computation…
The supersymmetric QCD corrections to the hadronic width of a heavy charged Higgs boson, basically dominated by the top-quark decay mode $H^{+}\rightarrow t \bar{b}$, are evaluated at ${\cal O}(\alpha_s)$ within the MSSM and compared with…
We present the first calculation of the two-loop electroweak fermionic correction to the flavour-dependent effective weak-mixing angle for bottom quarks, sin^2 theta_{eff}^{b anti-b}. For the evaluation of the missing two-loop vertex…
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 effective bottom Yukawa couplings are analyzed for the minimal supersymmetric extension of the Standard Model at two-loop accuracy within SUSY-QCD. They include the resummation of the dominant corrections for large values of tg(beta).…
The process $p \pbar \rightarrow W^{\pm}\gamma + X \rightarrow \ell^\pm \nu \gamma + X$ is calculated to ${\cal O}(\alpha_s)$ for general $CP$ conserving $WW\gamma$ couplings. At the Tevatron center of mass energy, the QCD corrections to…
The electroweak sphaleron rate in the high temperature phase of the Standard Model is inversely proportional to the weak-isospin conductivity. So far, only electroweak interactions were included in its computation. Here we take into account…
We calculate the supersymmetric ${\cal O}(\alpha_s)$ QCD corrections to stop and sbottom decays into vector bosons within the Minimal Supersymmetric Standard Model. We give analytic formulae and perform a numerical analysis of these decays.…
This article presents results for the last unknown two-loop contributions to the $Z$-boson partial widths and $Z$-peak cross-section. These are the so-called bosonic electroweak two-loop corrections, where "bosonic" refers to diagrams…