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J/Psi Absorption Scenarios in Nuclear Collisions

J. Geiss·E. Bratkovskaya·W. Cassing·C. Greiner
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Abstract

We study the production of $c \bar{c}$ pairs and dimuons from hard collisions in nuclear reactions within the covariant transport approach HSD. Adopting 6 mb for the $c \bar{c}$-baryon cross section the data on $J/Ψ$ suppression in p + A reactions are reproduced in line with calculations based on the Glauber model. Furthermore, using $J/Ψ$ absorption cross sections with mesons above the $D\bar{D}$ threshold in the order of 1.5 - 3 mb we find that all data on $J/Ψ$ suppression from NA38/NA50 can be described without assuming the formation of a quark-gluon plasma. Alternatively, we also investigate an 'early'-comover absorption scenario where the $c \bar{c}$ pairs are dissociated in the color electric fields of neighboring strings. Again we find good agreement with the experimental data with an estimate for the string radius of $R_s \approx 0.2-0.25 fm$.

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J. Geiss, E. Bratkovskaya, W. Cassing, C. Greiner. 1998-10-21. J/Psi Absorption Scenarios in Nuclear Collisions. https://arxiv.org/abs/nucl-th/9810059

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