Conference paper

Vector mesons ρ, ρ ′ and ρ ′′ diffractively photo- and leptoproduced

G. Kulzinger ; Institut für Theoretische Physik der Universität Heidelberg, Philosophenweg 16, 69120 Heidelberg, Germany

Abstract

In the framework of non-perturbative QCD, we calculate high-energy diffractive production of vector mesons ρ, ρ ′ and ρ ′′ by real and virtual photons on a nucleon. The initial photon dissociates into a qq¯-dipole and transforms into a vector meson by scattering off the nucleon which, for simplicity, is represented as quark-diquark. The relevant dipole-dipole scattering amplitude is provided by the non-perturbative model of the stochastic QCD vacuum. The wave functions result from considerations in the frame of light-front dynamics; the physical ρ ′ - and ρ ′′-mesons are assumed to be mixed states of an active 2S-excitation and some residual rest (2Dand/or hybrid state). We obtain good agreement with the experimental data and get an understanding of the markedly different π +π −-mass spectra for photoproduction and e+e –annihilation.

Keywords

non-perturbative QCD; diffraction; photoproduction; photon wave function; ρ-meson; excited vector mesons; hybrid state

Hrčak ID:

305363

URI

https://hrcak.srce.hr/305363

Publication date:

1.6.1999.

Article data in other languages: croatian

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