The Hard Diffraction in Vector Meson Production at HERA

TL;DR

This paper analyzes elastic vector meson production at HERA within perturbative QCD, examining energy dependence, polarization states, and production of heavier mesons like Psi' and Upsilon.

Contribution

It provides a comprehensive perturbative QCD analysis of vector meson production, including polarization measurements and energy dependence, covering multiple meson types.

Findings

Energy dependence of cross sections studied for J/Psi and rho.

Full polarization analysis including spin density matrix elements.

Discussion of heavier meson production like Psi' and Upsilon.

Abstract

Results on elastic vector meson production at HERA are presented in the framework of perturbative QCD. The energy dependence of the cross section for J/Psi photoproduction and for rho electroproduction is studied. A full polarisation analysis, including the measurement of the 15 elements of the spin density matrix and of R=sigma_L/sigma_T, is presented for rho electroproduction. Finally heavier vector mesons (Psi' and Upsilon) production is discussed.