Related papers: Two-loop electroweak fermionic corrections to sin^…
We compute the two-loop electroweak correction to the production of the Higgs boson in gluon fusion to higher orders in the dimensional-regularization parameter $\epsilon = (d-4)/2$. We employ the method of differential equations to compute…
We present the two-loop ${\cal O}(\alpha_sG_Fm_t^2)$ correction to the $b\bar b$ decay rate of the Stan\-dard-Model Higgs boson, assuming that the $t$ quark is much heavier than the Higgs boson. Apart from the universal correction connected…
We present the leading colour and light fermionic planar two-loop corrections for the production of two photons and a jet in the quark-antiquark and quark-gluon channels. In particular, we compute the interference of the two-loop amplitudes…
Details of the recent calculation of the two-loop bosonic corrections to the effective leptonic weak mixing angle are presented. In particular, the expansion in the difference of the W and Z boson masses is studied and some of the master…
The calculation of the two-loop corrections to the partial width of an intermediate-mass Higgs boson decaying into a pair of photons is reviewed. The main focus lies on the electroweak (EW) contributions. The sum of the EW corrections…
The four-loop QCD corrections to the electroweak $\rho$-parameter arising from top and bottom quark loops are computed. Specifically we evaluate the missing ``non-singlet'' piece. Using algebraic methods the amplitude is reduced to a set of…
Improved predictions for the Z-boson decay width and the hadronic Z-peak cross-section within the Standard Model are presented, based on a complete calculation of electroweak two-loop corrections with closed fermion loops. Compared to…
We calculate fermion-loop corrections to high energy $W^+W^-$ scattering in the context of a Strongly Interacting Electroweak Symmetry Breaking Sector (EWSBS) using Higgs Effective Field Theory(HEFT). We test the assumption that these…
We show that, unlike mass matrices, the fermionic gauge currents of the Standard Model exhibit, at the quantum level, remarkable SU(2)_f flavor properties at the observed values of the mixing angles. They accommodate all measured mixing for…
We study the asymptotic behaviour of two-loop electroweak corrections at energies Q >> M_W, where logarithms of the type ln(Q/M_W) become dominant. The calculation of the leading and next-to-leading logarithmic terms for massless and…
We revisit the contributions of order $\alpha^2(Z\alpha)^5m$ and $\alpha^2(Z\alpha)E_F$, respectively, to the Lamb shift and to the hyperfine splitting from mixed self-energy-vacuum-polarization diagrams, involving fermionic loop. We use…
We investigated the electroweak corrections from one-loop diagrams involving the third generation (s)quarks to the decay width of process $\tilde{\chi}_1^+ \to W^+ \tilde{\chi}_1^{0}$ in the framework of the Minimal Supersymmetric Standard…
We investigate the structure of the experimentally significant electroweak bosonic loop corrections to the leptonic weak mixing angle, the leptonic Z-boson decay width, and the W-boson mass. It is shown that the bosonic corrections that…
In order to test the accuracy of the Heavy Top-mass Expansion (HTE) employed in recent two-loop calculations of MW and sin^2theta_eff, we consider their contributions to subtracted quantities of the form MW_sub=MW(mh)-MW(mh0), where mh0 is…
We compute the dominant two-loop electroweak correction, of O(G_F M_t^2), to the partial width of the decay of an intermediate-mass Higgs boson into a pair of photons. We use the asymptotic-expansion technique in order to extract the…
We calculate a two-loop effective potential to the order of {\cal O}(\lambda_t^2\alpha_s) in the MSSM. We then study the corresponding two-loop corrections to the CP-even Higgs-boson mass for arbitrary \tan\beta and left-right top-squark…
We present the calculation of the mixed two-loop QCD/electroweak corrections to hadronic W boson decays within the Standard Model. The optical theorem is applied to the W boson two-point function. The multi-scale integrals are computed with…
In this talk \footnote{Presented at ICHEP'98, Vancouver, CA, July 1998}, we present a recently suggested way on how to analytically incorporate massive threshold effects into observables calculated in massless QCD. No matching is required…
In calculating electroweak radiative corrections at two-loop level, one encounters Feynman graphs with several different masses on the internal propagators and on the external legs, which lead to complicated scalar functions. We describe a…
We discuss the full electroweak one-loop corrections to the decay of the pseudoscalar Higgs boson A^0 into two sfermions within the Minimal Supersymmetric Standard Model. In particular, we consider the sfermions of the third generation,…