Do direct leptons with large transverse momentum originate from ψ production?

Abstract

We show that the energy as well as the transverse momentum dependence of the yield of direct leptons in pp collisions can be obtained from the production and subsequent decay of vector mesons (ϱ, ω, φ and ψ). This firstly requires that the total ψ yield σ(pp→ ψ) be 0.02 μb at 70 GeV, ≈ 2 μb at 300 GeV, 3–10 μb at 1500 GeV and secondly that the transverse momentum distribution be broader than that of other hadrons, with 〈p T 2〉 ≳ 0.5 (GeV/c) 2.