Related papers: Two-loop electroweak Sudakov logarithms for massiv…
We study radiative corrections to third generation scalar fermions into gauge bosons $Z$ and $W^\pm$. We include both SUSY-QCD, QED and full electroweak corrections. It is found that the electroweak corrections can be of the same order as…
Jet cross sections at high-energy colliders exhibit intricate patterns of logarithmically enhanced higher-order corrections. In particular, so-called non-global logarithms emerge from soft radiation emitted off energetic partons inside…
It has been known for many years that jet cross sections at hadron colliders exhibit double-logarithmic corrections starting at four-loop order, arising from two soft Glauber-gluon interactions between the two colliding partons. The…
The Standard Model (SM) prediction of the top quark forward backward asymmetry is shown to be slightly enhanced by a correction factor of 1.05 due to electroweak Sudakov (EWS) logarithms of the form (\alpha/sin^2 \theta_W)^n log^{m< 2n}…
Four-fermion processes with a particle lost in the beam pipe are studied at LEP to perform precision tests of the electroweak theory. Leading higher-order QED corrections to such processes are analyzed within the framework of the Structure…
A new dynamical symmetry breaking of $SU(2)_{L}\times U(1)$ caused by the combination of the axial-vector component and the fermion mass is found in electroweak theory. We obtain (m^{2}_{W}={1/2}g^{2}m^{2}_{t}) and (m^{2}_{Z}=\rho…
In order to investigate the systematics of the loop expansion in high temperature gauge theories beyond the leading order hard thermal loop (HTL) approximation, we calculate the two-loop electron proper self-energy in high temperature QED.…
We compute the complete two-loop O(alpha) Wilson coefficients relevant for radiative decays of the B meson in the SM. This is a necessary step in the calculation of the O(alpha alpha_s^n ln^n m_b/M_W) corrections and improves on our…
For superpartner masses not much heavier than the weak scale $M=M_{\rm W}$, large logarithmic corrections of the Sudakov type arise at TeV energies. In this paper we discuss the general structure of electroweak supersymmetric (susy) Sudakov…
We study $N$-jettiness in electroweak processes at extreme high energies. The description of the scattering process such as $e^- e^+ \rightarrow \mu^- \mu^+ +X$ is similar to QCD. At present, electroweak processes are prevailed by the…
We compute two-loop electroweak corrections to double Higgs boson production in gluon fusion mediated by light quarks in a fully analytical way. We determine a basis of master integrals satisfying canonical differential equations in…
We investigate the origin of the double logarithms of Q^2/m_c^2 that appear in the calculation of the cross section for e+e- -> J/psi + eta_c at next-to-leading order in alpha_s. We find that, diagram-by-diagram, the double logarithms are…
The aim of the thesis is to study models of the electroweak symmetry breaking caused by dynamically generated masses of quarks and leptons. (1) We perform the basic analysis whether the main underlying idea, that the masses of only known…
We study the impact of electroweak radiative corrections on direct production of photons with high transverse momenta at hadron colliders. Analytic results for the weak one-loop corrections to the parton scattering reaction $\bar q q \to…
Two-loop corrections for the form factor in a massive Abelian theory are evaluated, which result from the insertion of massless fermion or scalar loops into the massive gauge boson propagator. The result is valid for arbitrary energies and…
The two-loop electron self-energy correction is one of the most problematic QED effects and, for a long time, was the dominant source of uncertainty in the theoretical prediction of the bound-electron $g$ factor in hydrogen-like ions. A…
We report a calculation of all two-loop QED corrections with closed fermion loops for the n=1 and n=2 states of H-like ions and for a wide range of the nuclear charge numbers Z=1-100. The calculation is performed to all orders in the…
We compute the leading logarithms electroweak contributions to gamma gamma to f f(bar) processes in SM and MSSM. Several interesting properties are pointed out, such as the importance of the angular dependent terms, of the Yukawa terms, and…
We have calculated the fermion contributions to the shift of the position of the poles of the massive gauge boson propagators at two-loop order in the Standard Model. Together with the bosonic contributions calculated previously the full…
We perform a dedicated study of the $q \bar{q}$-initiated two-loop electroweak-QCD Drell-Yan scattering amplitude in dimensional regularization schemes for vanishing light quark and lepton masses. For the relative order $\alpha$ and…