2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/94952The process of the muon (pion) pair production with small invariant mass in the electron--positron high--energy annihilation, accompanied by emission of hard photon at large angles, is considered. We find that the Drell--Yan picture for differential cross section is valid in the charge--even experimental set--up. Radiative corrections both for electron block and for final state block are taken into account.14 pages, 2 figuresHigh Energy Physics - Phenomenologytext