Compton scattering of quasi-real virtual photons at LEP

Abstract Compton scattering of quasi-real virtual photons, γ e ± → γ e ± , is studied with 0.6 fb −1 of data collected by the L3 detector at the LEP e + e − collider at centre-of-mass energies s = 189 – 209 GeV . About 4500 events produced by the interaction of virtual photons emitted by e ± of one beam with e ∓ of the opposite beam are collected for effective centre-of-mass energies of the photon–electron and photon–positron systems in the range from s ′ = 35 GeV up to s ′ = 175 GeV , the highest energy at which Compton scattering was ever probed. The cross sections of the γ e ± → γ e ± process as a function of s ′ and of the rest-frame scattering angle are measured, combined with previous L3 measurements down to s ′ ≃ 20 GeV , and found to agree with the QED expectations.