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arXiv · hep-ph/9810370

Vector-Meson Electroproduction from Generalized Vector Dominance

Abstract

Including destructively interfering off-diagonal transitions of diffraction-dissociation type, we arrive at a formulation of GVD for exclusive vector-meson production in terms of a continuous spectral representation of dipole form. The transverse cross-section sigma_T for gamma* p -> V p behaves asymptotically as 1/Q^4, while R_V = sigma_L/sigma_T becomes asymptotically constant. Contributions violating s-channel helicity conservation stay at the 10-15% level established in low-energy photoproduction and diffractive hadron--hadron interactions. The data for phi- and rho-meson production for 0 \lsim Q^2 \lsim 20 GeV^2 from HERA are found to be in agreement with these predictions.

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BibTeXRIS

Dieter Schildknecht, Gerhard A. Schuler, Bernd Surrow. 1998-10-15. Vector-Meson Electroproduction from Generalized Vector Dominance. https://doi.org/10.1016/s0370-2693(99)00052-0

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