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We calculate the Coulomb effects on the cross section for e + e − → W + W − taking into account the instability of the W bosons. We carefully explain the consequences of instability throughout the energy range which will be accessible at LEP2. We present a formula which allows these effects to be easily implemented.----- †

We present a "theorem" which quantifies, for inclusive processes, the level of suppression of the radiative interference effects between the production and decay stages of heavy unstable particles. The theorem, which is based on very general physical arguments, is applicable to all orders in the coupling.

Aimed at graduate students and researchers in theoretical physics, this book presents the modern theory of strong interaction: quantum chromodynamics (QCD).The book exposes various perturbative and nonperturbative approaches to the theory, including chiral effective theory, the problems of anomalies, vacuum tunnel transitions, and the problem of divergence of the perturbative series. The QCD sum rules approach is exposed in detail. A great variety of hadronic properties (masses of mesons and baryons, magnetic moments, formfactors, quark distributions in hadrons, etc.) have been found using this method. The evolution of hadronic structure functions is presented in detail, together with polarization phenomena. The problem of jets in QCD is treated through theoretical description and experimental observation. The connection with Regge theory is emphasized. The book covers many aspects of theory which are not discussed in other books, such as CET, QCD sum rules, and BFKL. B . L . I O FF E is Head of the Laboratory of Theoretical Physics at ITEP, Moscow. He discovered the origin of baryon masses in QCD, the light-cone dominance in deep inelastic scattering. He predicted that parity violation in weak interactions should be accompanied by violation of charge symmetry or time reversal invariance, and the observation of parity violating spin-momentum correlations would mean the charge symmetry violation. He has won several prizes, including the Alexander von Humboldt Award. V. S . FA D I N is Head of the Theoretical Department of the Budker Institute of Nuclear Physics. He is one of the authors of the BFKL equation for parton distributions, which gives the most common basis for the theoretical description of semi-hard processes. He is also one of the discoverers of the coherence effect in gluon emission, which is crucial for inclusive spectra of hadrons in their soft region. L . N . L I PAT OV is Director of the Theoretical Physics Department at the Institute for Nuclear Physics, St. Petersburg. He is one of the authors of the DGLAP and BFKL equations for the parton distributions used in the theoretical description of the deep inelastic ep scattering and other processes in QCD. He has been awarded prizes from the ITEP and FIAN institutes for outstanding scientific achievements.

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The QED Coulomb correction is one of the most important corrections to the e + e − → W + W − total cross section near threshold. We calculate these corrections through second order, and discuss the implications for extracting M W from a threshold cross section measurement at LEP2. Analytic expressions are derived in various kinematic limits.

An electron pole approximation is presented, which can be used to calculate cross-sections in high energy quantum electrodynamics. A general derivation is given and some applications are considered : 1) bremsstrahlung in electron-electron (positron) collisions at large angles ; 2) photoproduction and electroproduction of a pair of particles on an electron at large angles ; 3) photon emission at a large angle when the cross-section does not decrease with energy ; 4) total cross-section for muon pair production in electron-positron collisions via one photon. The case of polarized particles is also discussed