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Parton Cascade Description of Heavy-Ion Collisions at CERN ?

Klaus Geiger
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Abstract

There seems to be a general consensus now that a first glimpse of a QGP-like effect has become visible in the beautiful NA50 data on J/ψproduction and the `anomalous supression' phenomenon. On the other hand, it is still widely believed that the dynamics of heavy-ion collisions at CERN SPS energy is predominantly governed by soft, non-perturbative physics. This is ironic: after all, it is unlikely that a QGP could be formed if the underlying dynamics were essentyially soft, rather than that it requires intense quark-gluon production with sufficient cascade-like reinteractions which drive the matter to large density and equilibrium. Therefore, I advocate in this contribution that for ultra-relativistic nucleus-nucleus collisions a description based on the pQCD interactions and cascade evolution of involved partons can and should be used, owing to the claim that short-range parton interactions play an important role at sufficiently high beam energies, including CERN energy sqrt(s) = 20 A GeV. Here mini-jet production which liberates of quarks and gluons cannot be considered as an isolated rare phenomenon, but can occur quite copiously and may lead to complex multiple cascade-type processes.

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Klaus Geiger. 1998-01-06. Parton Cascade Description of Heavy-Ion Collisions at CERN ?. https://doi.org/10.1016/s0375-9474(98)00377-7

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