Weak interactions of colliding lepton beams with energy 10 2–10 3 GeV

Abstract

Weak V-A interaction of colliding lepton beams at high energies is considered. It is assumed that the weak coupling constant G is the only parameter inherent to the weak leptonic interaction so that terms of higher order become appreciable at total energy 2E = s 1 2 of order G − 1 2 . It is shown that for colliding lepton-antilepton beams 2 × 250 GeV, the contribution of weak interactions to the differential cross section of elastic scattering at angle θ ⋍ 90° prevails over that of electromagnetic interaction. The estimate of the weak cross section is based on the calculation of the imaginary part of the amplitude which is uniquely determined in the second order in G. Phenomenological description of the real part of the amplitude in the same approximation introduces a single unknown parameter. Provided the validity of dispersion relations with two subtractions is granted this parameter is related to the integral of total cross sections of ℓℓ and ℓ ℓ weak interactions. Terms of the third order in G are studied in a similar way and an estimation of the magnitude of these terms is given.