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arXiv · hep-ph/0612043

A systematic study of J/psi suppression in cold nuclear matter

Abstract

Based on a Glauber model, a statistical analysis of all mid-rapidity J/psi hadroproduction and leptoproduction data on nuclear targets is carried out. This allows us to determine the J/psi-nucleon inelastic cross section, whose knowledge is crucial to interpret the J/psi suppression observed in heavy-ion collisions, at SPS and at RHIC. The values of sigma are extracted from each experiment. A clear tension between the different data sets is reported. The global fit of all data gives sigma=3.4+/-0.2 mb, which is significantly smaller than previous estimates. A similar value, sigma=3.5+/-0.2 mb, is obtained when the nDS nuclear parton densities are included in the analysis, although we emphasize that the present uncertainties on gluon (anti)shadowing do not allow for a precise determination of sigma. Finally, no significant energy dependence of the J/psi-N interaction is observed, unless strong nuclear modifications of the parton densities are assumed.

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Francois Arleo, Vi-Nham Tram. 2006-12-05. A systematic study of J/psi suppression in cold nuclear matter. https://doi.org/10.1140/epjc%2Fs10052-008-0604-8

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