Related papers: Large angle QED processes at e^+e^- colliders at e…
We describe in detail the calculation of the two-loop corrections to the QED Bhabha scattering cross section due to the vacuum polarization by heavy fermions. Our approach eliminates one mass scale from the most challenging part of the…
Heavy hadron production in $e^+e^-$ annihilation is studied in the framework of heavy-quark recombination mechanism. This mechanism predicts a new type of 3-jet event such as $b\bar{b}q$ or $b\bar{b}\bar{q}$, which is power-suppressed…
Analytic formulae are derived for the complete photon energy spectrum due to QED corrections to fermion pair production in case of a limited angular acceptance for the final state fermions. After a numerical integration over the energy of…
We consider quantum electrodynamics (QED) corrections to the fine splitting $E(2P_{3/2}) - E(2P_{1/2})$ in the Li atom. We derive complete formulas for the $m\,\alpha^6$ and $m\,\alpha^7\,\ln\alpha$ contributions and calculate them…
Theoretical predictions for Bhabha scattering observables are presented including complete one-loop electroweak radiative corrections. A longitudinal polarization of the initial beams is taken into account. Numerical results for the…
We have calculated the complete O(alpha) and O(alpha_s) radiative corrections to the Higgs-production process e+ e- -> t anti-t H in the Standard Model. This process is particularly interesting for the measurement of the top-quark Yukawa…
The total cross section for Compton scattering off atomic electrons, $\gamma+e\rightarrow\gamma'+e'$, was measured using photons with energies between 6.5 and 11.1 GeV incident on a $^9$Be target as part of the PrimEx-eta experiment in Hall…
We review high--energy scattering processes that are sensitive to the hadronic structure of the photon, describing theoretical predictions as well as recent experimental results. These processes include deep--inelastic electron--photon…
We perform a detailed study of the process $e^+e^-\to \mu^+\mu^-\nu_l\bar\nu_l$ including all contributions. The contributions other than from real gauge boson production leads to a rich phenomenology. We explore the use of the process as a…
The lowest order radiative correction to the differential cross-section of process of muon pair production with emission of hard photon at high energy electron-positron annihilation are calculated. Taking into account the emission of…
The differential cross sections of the p^{10}B scattering at energies of 197, 600 and 1000 MeV have been calculated within the framework of the Glauber theory. The operator of multiple scattering takes into account the contributions of…
The process e+e- to 2 (or 3) gammas is studied using data recorded with the OPAL detector at LEP. The data sample taken at a centre-of-mass energy of 189 GeV corresponds to a total integrated luminosity of 178 pb-1. The measured…
We evaluate several basic electrodynamic processes as modified by the presence of a very strong magnetic field, exceeding $B_{\rm Q} \equiv m^2/e = 4.4\times 10^{13}$ G. These results are needed to build models of dissipative phenomena…
I survey a number of interesting tests of quantum chromodynamics at the amplitude level which can be carried out in electron-positron annihilation and in photon-photon collisions at low energy, including measurements of fundamental…
We evaluate the QED corrections due to initial state radiation (ISR) to associated Higgs boson production in electron-positron ($e^+ e^-$) annihilation at typical energies of interest for the measurement of the Higgs properties at future…
Selected applications of perturbative Quantumchromodynamics (QCD) to predictions of the Standard Model for processes at high energy colliders are reviewed with emphasis on past successes and future problems. This is a personal retrospective…
The construction of a computer code to calculate the cross sections for the spin-polarized processes e-gamma=>e-gamma,e-gamma-gamma,e-e+e- to order-alpha**3 is described. The code calculates cross sections for circularly-polarized…
The four-fermion contact-interaction searches in the process $e^+e^-\to\mu^+\mu^-$ at a future $e^+e^-$ Linear Collider with c.m. energy $\sqrt{s}=0.5$ TeV and with both beams longitudinally polarized are studied. We evaluate the…
Experimental tests of QCD predictions for event shape distributions combining contributions from hard and soft processes are discussed. The hard processes are predicted by perturbative QCD calculations. The soft processes cannot be…
The study of Bhabha scattering at e^+e^- colliders probes the running of the electromagnetic coupling. After early measurements by the VENUS collaboration at TRISTAN and the by L3 collaboration at LEP, two recent analyses have been…