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Charmonium Production in gamma-A, p-A and A-A

L. Gerland
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Abstract

The data for the production of the $ψ'$ meson in pA collisions at 450 GeV at CERN-SPS (of the NA50-collaboration) yields $σ(ψ' N)\approx 8$ mb under the assumption that the $ψ'$ is produced as a result of the space-time evolution of a point-like $c\bar c$ pair which expands with time to the full size of the charmonium state. However, much higher values of $σ(ψ' N)$ are not ruled out by the data. We show that recent CERN data confirm the suggestion that color fluctuations are the major source of suppression of the $J/ψ$ yield as observed at CERN in both pA and AA collisions.

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L. Gerland. 2003-07-28. Charmonium Production in gamma-A, p-A and A-A. https://doi.org/10.1088/0954-3899%2F30%2F1%2F058

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