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arXiv · hep-ph/9902337

Modelling J/psi production and absorption in a microscopic nonequilibrium approach

C. Spieles·R. Vogt·L. Gerland·S. A. Bass·M. Bleicher·H. Stoecker·W. Greiner
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Abstract

Charmonium production and absorption in heavy ion collisions is studied with the Ultrarelativisitic Quantum Molecular Dynamics model. We compare the scenario of universal and time independent color-octet dissociation cross sections with one of distinct color-singlet J/psi, psi' and chi_c states, evolving from small, color transparent configurations to their asymptotic sizes. The measured J/psi production cross sections in pA and AB collisions at SPS energies are consistent with both - purely hadronic - scenarios. The predicted rapidity dependence of J/psi suppression can be used to discriminate between the two experimentally. The importance of interactions with secondary hadrons and the applicability of thermal reaction kinetics to J/psi absorption are investigated. We discuss the effect of nuclear stopping and the role of leading hadrons. The dependence of the psi' to J/psi ratio on the model assumptions and the possible influence of refeeding processes is also studied.

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C. Spieles, R. Vogt, L. Gerland, S. A. Bass, M. Bleicher, H. Stoecker, W. Greiner. 1999-02-13. Modelling J/psi production and absorption in a microscopic nonequilibrium approach. https://doi.org/10.1103/physrevc.60.054901

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