Related papers: The Callan-Symanzik equation of the electroweak St…
In quantum electrodynamics with fermions f = e,\mu..., knowledge of the vacuum polarization spectral function determined from the tree level e^+e^- -> f^+f^- cross sections, together with a single low energy measurement of the fine…
The one-loop renormalizability of the electroweak sector of the Standard Model Extension with Lorentz violation is studied. Functional determinants are used to calculate the one-loop contributions of the higgs, gauge bosons and fermions to…
Callan-Symanzik and renormalization group equation are discussed for the $U(1)$-axial model and it is shown that the symmetric model is not the asymptotic version of the spontaneously broken one due to mass logarithms in the…
An exact evolution equation, the functional generalization of the Callan-Symanzik method, is given for the effective action of QED where the electron mass is used to turn the quantum fluctuations on gradually. The usual renormalization…
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 study, in the Minimal Supersymmetric Standard Model, the electroweak symmetry breaking conditions obtained from the one-loop effective potential. Novel model-independent lower and upper bounds on $\tan \beta$, involving the other free…
In this paper, we consider the $\beta$ function at one-loop approximation for noncommutative scalar QED. The renormalization of the full theory, including the basic vertices, and the renormalization group equation are fully established.…
The effective renormalizable theory describing electromagnetic and strong interactions of quarks of five light flavors ($n_f = 5$ QCD$\times$QED) is considered as a low-energy limit of the full Standard Model. Two-loop relation between the…
The running of the effective electromagnetic coupling is for many electroweak observables the dominant correction. It plays an important role for deriving constraints on the Standard Model in the context of electroweak precision…
Recently exact results for the complete fermionic two-loop contributions to the prediction for the W-boson mass from muon decay in the electroweak Standard Model have been published [hep-ph/0007091]. This paper illustrates the techniques…
We report on how a straightforward (albeit technically involved) analytic study of the 1-loop effective potential in the Minimal Supersymmetric Standard Model, modifies the usual electroweak symmetry breaking conditions involving $\tan…
We calculate the virtual electroweak Sudakov (double) logarithms at one- and two-loop level for arbitrary on-shell/on-resonance particles in the Standard Model. The associated Sudakov form factors apply in a universal way to arbitrary…
We present analytical results at four-loop level for the $\beta$-function of the coupling of a generic gauge group and any number of different quark representations. From this we can directly derive the gluino contribution to the strong…
The Standard Model is one of the main intellectual achievements for about the last 50 years, a result of many theoretical and experimental studies. In this lecture a brief introduction to the electroweak part of the Standard Model is given.…
A comprehensive analysis on the photon self-energy, the fermion self-energy, and the fermion vertex function is presented at one loop in the context of quantum electrodynamics (QED) with 1 extra dimension. In 5-dimensional theories,…
Two-loop $\beta$-function and anomalous dimension are calculated for N=1 supersymmetric quantum electrodynamics, regularized by higher derivatives in the minimal subtraction scheme. The result for two-loop contribution to the…
We investigate the electroweak phase transition in the real-singlet extension of the Standard Model at two-loop level, building upon existing one-loop studies. We calculate the effective potential in the high-temperature approximation and…
We consider two-loop leading and next-to-leading logarithmic virtual corrections to arbitrary processes with external massless fermions in the electroweak Standard Model at energies well above the electroweak scale. Using the…
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 describe the main building blocks of a generic automated package for the calculation of Feynman diagrams. These blocks include the generation and creation of a model file, the graph generation, the symbolic calculation at an intermediate…