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Strangeness Enhancement in $p+A$ and $S+A$ Interactions at SPS Energies

V. Topor Pop·M. Gyulassy·X. N. Wang·A. Andrighetto·M. Morando·F. Pellegrini·R. A. Ricci·G. Segato
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Abstract

The systematics of strangeness enhancement is calculated using the HIJING and VENUS models and compared to recent data on $\,pp\,$, $\,pA\,$ and $\,AA\,$ collisions at CERN/SPS energies ($200A\,\, GeV\,$). The HIJING model is used to perform a {\em linear} extrapolation from $pp$ to $AA$. VENUS is used to estimate the effects of final state cascading and possible non-conventional production mechanisms. This comparison shows that the large enhancement of strangeness observed in $S+Au$ collisions, interpreted previously as possible evidence for quark-gluon plasma formation, has its origins in non-equilibrium dynamics of few nucleon systems. % Strangeness enhancement %is therefore traced back to the change in the production dynamics %from $pp$ to minimum bias $pS$ and central $SS$ collisions. A factor of two enhancement of $Λ^{0}$ at mid-rapidity is indicated by recent $pS$ data, where on the average {\em one} projectile nucleon interacts with only {\em two} target nucleons. There appears to be another factor of two enhancement in the light ion reaction $SS$ relative to $pS$, when on the average only two projectile nucleons interact with two target ones.

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V. Topor Pop, M. Gyulassy, X. N. Wang, A. Andrighetto, M. Morando, F. Pellegrini, R. A. Ricci, G. Segato. 1995-04-05. Strangeness Enhancement in $p+A$ and $S+A$ Interactions at SPS Energies. https://doi.org/10.1103/physrevc.52.1618

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