Generalized vector-dominance model for lepton production at large transverse momenta

The direct production of leptons at large transverse momenta p is studied in the framework of generalized vector dominance (GVD). A simple model is constructed for inclusive vector-meson production that accounts for all available data at large and small p. The muon-pair distributions as functions of the muon-pair mass are calculated in fair agreement with experiment. It is shown that the old vector mesons rho, ω, phi together with their GVD partners and the new particles psi', psi' can account for all the observed large-p lepton yields