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Inelastic $J/Ψ$ Photoproduction off Nuclei: Gluon Enhancement or Double Color Exchange?

J. Huefner·B. Z. Kopeliovich·Al. B. Zamolodchikov
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Abstract

The nuclear enhancement observed in inelastic photoproduction of $J/Ψ$ should not be interpreted as evidence for an increased gluon density in nuclei. The nuclear suppression of the production rate due to initial and final state interactions is calculated and a novel two-step color exchange process is proposed, which is able to explain the data.

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J. Huefner, B. Z. Kopeliovich, Al. B. Zamolodchikov. 1996-07-17. Inelastic $J/Ψ$ Photoproduction off Nuclei: Gluon Enhancement or Double Color Exchange?. https://doi.org/10.1007/s002180050222

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