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arXiv · hep-ph/9812316

Diffractive Photoproduction of $Υ$ at HERA

L. L. Frankfurt·M. F. McDermott·M. Strikman
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Abstract

Predictions for the diffractive photoproduction of the $Υ$-family at HERA energies, within the framework of the analysis by Frankfurt, Koepf and Strikman, are presented. Two novel effects lead to a significant enhancement of the original calculation: the non-diagonal (or skewed) kinematics, calculated to leading-log($Q^2$) accuracy, and the large magnitude of the real part of the amplitude. The resultant cross sections are found to agree fairly well with recent preliminary data from ZEUS and H1. A strong correlation between the mass of the diffractively produced state and the energy dependence of the cross section is found. In particular, a considerably stronger rise in energy is predicted than that found in $J/ψ$-production.

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L. L. Frankfurt, M. F. McDermott, M. Strikman. 1999-04-08. Diffractive Photoproduction of $Υ$ at HERA. https://doi.org/10.1088/1126-6708%2F1999%2F02%2F002

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