Elastic electroproduction of ϱ and [formula omitted] mesons at large Q2 at HERA

Abstract

The total cross sections for the elastic electroproduction of P and J ψ mesons for Q 2 > 8 GeV 2 and 〈W〉 ⋍ 90 GeV/c 2 are measured at HERA with the H1 detector. The measurements are for an integrated electron-proton luminosity of ⋍3 pb −1 . The dependences of the total virtual photon-proton ( γ ∗p ) cross sections on Q 2, W and the momentum transfer squared to the proton ( t), and, for the ϱ, the dependence on the polar decay angle ( cos θ ∗ are presented. The J ψ : ∂ cross section ratio is determined. The results are discussed in the light of theoretical models and of the interplay of hard and soft physics processes.