Related papers: Three-Loop Corrections to Lamb Shift in Positroniu…
Self-energy corrections to the energy levels of bound electrons are calculated in the framework of path integrals. We arrive at the full fermion propagator, using methods of functional integrals, in the form of Schwinger-Dyson equation…
We report on recent progress in the calculation of the 3-loop massive Wilson coefficients in deep-inelastic scattering at general values of $N$ for neutral and charged current reactions in the asymptotic region $Q^2 \gg m^2$. Four new out…
The contribution of the $\alpha^3$ single electron-loop vacuum-polarization diagrams to the Lamb shift of the muonic hydrogen has been evaluated recently by two independent methods. One uses the exact parametric representation of the…
Order $\alpha^2$ corrections to the decay rate of parapositronium are calculated. A QED scattering calculation of the amplitude for electron-positron annihilation into two photons at threshold is combined with the technique of effective…
We consider the $1s$ Lamb shift in hydrogen and helium ions, a quantity, required for an accurate determination of the Rydberg constant and the proton charge radius by means of hydrogen spectroscopy, as well as for precision tests of the…
We compute the three-loop corrections to the potential of two heavy quarks. In particular we consider in this Letter the purely gluonic contribution which provides in combination with the fermion corrections of Ref. \cite{Smirnov:2008pn}…
Although one-loop calculations provide a realistic description of bulk and single-particle nuclear properties, it is necessary to examine loop corrections to develop a systematic finite-density power-counting scheme for the nuclear…
The three-loop vacuum polarization function $\Pi(q^2)$ induced by a massive quark is calculated. A comprehensive description of the method is presented. From the imaginary part the ${\cal O}(\alpha_s^2)$ result for the production of heavy…
We calculate the first Coulomb correction to the spectra of two processes: the electron bremsstrahlung and electron-positron photoproduction in the Coulomb field. We show that, in contrast to the results obtained in the Born approximation…
We calculate the leading Coulomb correction to the energy loss in the electron-nucleus Bremsstrahlung for arbitrary energy of the incoming particle. This correction determines the charge asymmetry, i.e., the difference of electron and…
The spin effect of electrons/positrons ($e^-$/$e^+$) and polarization effect of $\gamma$ photons are investigated in the interaction of two counter-propagating linearly polarized 10-PW-class laser pulses with a thin foil target. The…
The energy levels of the $n=1$ and $n=2$ bound states of the $\mu^+\mu^-$ atom (true muonium) are calculated starting from a previously derived potential that correctly describes positronium to order $\alpha^5$ supplemented by the known…
Within the framework of the standard quantum electrodynamics, we compute contribution of vacuum polarization at one-loop order to the power spectrum of the magnetic field on inflationary (de Sitter) background. It is found that the one-loop…
First correction to the high-energy asymptotics of the total $e^+e^-$ photoproduction cross section in the electric field of a heavy atom is obtained with the exact account of this field. The consideration is based on the use of the…
Full one-loop electroweak-corrections for an $e^-e^+\rightarrow t \bar{t}$ process associated with sequential $t\rightarrow b \mu\nu_\mu$ decay are discussed. At the one-loop level, the spin-polarization effects of the initial electron and…
We present a numerical evaluation of the loop-after-loop contribution to the second-order self-energy for the ground state of hydrogenlike atoms with low nuclear charge numbers Z. The calculation is carried out in the Fried-Yennie gauge and…
Photon-graviton mixing in an electromagnetic field is a process of potential interest for cosmology and astrophysics. At the tree level it has been studied by many authors. We consider the one-loop contribution to this amplitude involving a…
The radiative corrections to elastic electron-proton scattering are analyzed in a hadronic model including the finite size of the nucleon. For initial electron energies above 8 GeV and large scattering angles, the proton vertex correction…
We study the one-loop radiative corrections to pair production of the supersymmetric scalar partners of the standard fermions in e+e- annihilation. Both electroweak and SUSY-QCD corrections are considered. Applications are for production of…
A detailed description of the numerical procedure is presented for the evaluation of the one-loop self-energy correction to the $g$-factor of an electron in the $1s$ and $2s$ states in H-like ions to all orders in $Z\alpha$.