Proton Dissociative Rho and Elastic Phi Electroproduction at HERA

TL;DR

This paper investigates the production mechanisms and cross section ratios of rho and Phi mesons in electron-proton collisions at HERA, providing insights into diffractive processes and vector meson polarization at high Q^2.

Contribution

It presents new measurements of cross sections, polarization, and ratios for rho and Phi mesons, testing the factorization hypothesis in diffractive electroproduction.

Findings

Measured cross section dependence on P_t^2 and Q^2.

Determined the ratio of proton dissociative to elastic rho production.

Analyzed the Q^2 dependence of the Phi to rho elastic cross section ratio.

Abstract

The electroproduction of rho mesons with proton diffractive dissociation for Q^2 > 7 GeV^2 and the elastic electroproduction of Phi mesons for Q^2 > 6 Gev^2 are studied in e^+ p collisions at HERA with the H1 detector, for an integrated luminosity of 2.8 pb-1. The dependence of the cross sections on P_t^2 and Q^2 is measured, and the vector meson polarisation obtained. The cross section ratio between proton dissociative and elastic production of rho mesons is measured and discussed in the framework of the factorisation hypothesis of diffractive vertices. The ratio of the elastic cross section for Phi and rho meson production is investigated as a function of Q^2.