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arXiv · hep-ph/9807294

Fermi Motion and Quark Off-Shellness in Elastic Vector-Meson Production

I. Royen·J. R. Cudell
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Abstract

We study ways of implementing Fermi momentum in elastic vector-meson production, and find that the usual on-shell assumption of quark models and quark wave functions cannot reproduce the ratio of the longitudinal cross section to the transverse one. We propose a new approach which allows the quarks to be off-shell, and which naturally reproduces the data. As a consequence, we prove that the asymptotic form of the transverse cross section is different from 1/Q^8. In this new model, we show that the mass, t and Q2 dependence of the cross sections are also reproduced. We also make predictions concerning the production of excited states such as the rho' and the psi'.

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I. Royen, J. R. Cudell. 1998-12-03. Fermi Motion and Quark Off-Shellness in Elastic Vector-Meson Production. https://doi.org/10.1016/s0550-3213(98)00858-x

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