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

Summary  The direct production of leptons at large transverse momentap ⊥ 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 smallp ⊥. 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 ρ, ω, ϕ together with their GVD partners and the new particles ψ, ψ′ can account for all the observed large-p ⊥ lepton yields.