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$J/ψ$ normal and anomalous suppressions in a hadron and string cascade model

Sa Ben-Hao·Amand Faessler·Tai An·T. Waindzoch·C. Fuchs·Z. S. Wang·Wang Hui
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Abstract

A mechanism for the effective dissociation of a $c\bar{c}$ pair in the colour electric field of strings is introduced into a hadron and string cascade model, i.e. JPCIAE, which is based on the LUND model, simulating ultra-relativistic nucleus - nucleus collisions. This new mechanism together with the known mechanism of nuclear absorption (both baryons and mesons) could reproduce fairly the data of the normal and anomalous $J/ψ$ suppressions in minimum bias pA, AB (with light projectile), and Pb + Pb collisions at 200 A GeV/c. However the impact parameter (E_T) dependence of the $J/ψ$ suppression factor, both, in S + U and Pb + Pb reactions at 200 A GeV/c and 158 A GeV/c, respectively, is not well reproduced. We also tested the additional mechanism of the energy degradation of leading particles, with which both, the normal and anomalous $J/ψ$ suppressions in minimum bias pA, AB, and Pb + Pb collisions and the E_T dependence of the $J/ψ$ suppression factor are better reproduced.

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Sa Ben-Hao, Amand Faessler, Tai An, T. Waindzoch, C. Fuchs, Z. S. Wang, Wang Hui. 1999-02-19. $J/ψ$ normal and anomalous suppressions in a hadron and string cascade model. https://doi.org/10.1088/0954-3899%2F25%2F6%2F302

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