Hard-photon emission in e +e − reactions

Abstract

The radiative corrections to lowest order for the reactions e +e − giving any final state f, different from e +e −, are calculated, taking into account the contributions coming from the photons emitted by the electrons. Then an application of these results to the process e +e − → π + π − is done in the experimental conditions of ACO. The difference with previous results arises from: (i) a rigorous calculation of Feynman diagrams without using the “quasi-réel” process approximation, (ii) the error in the Coulomb terms, and (iii) a precise evaluation of the photon phase space.