The linear coalescence approach to hadronization of quark matter is shown to have problems with strangeness conservation in a baryon rich environment. The simplest correct quark counting is shown to ...coincide with the non-linear
algebraic
coalescence
rehadronization model, ALCOR. We argue that experimental facts agree with the assumption that quark degrees of freedom are liberated before hadron formation in 158 AGeV central Pb + Pb collisions at CERN SPS.
Since the beginning of the efforts to produce and understand quark matter large changes developed in the ideas of description of this matter. In the present paper we summarize some aspects of this ...development.
Results of resonance searches in the Xi(-)pi(-), Xi(-)pi(+), Xi;(+)pi(-), and Xi;(+)pi(+) invariant mass spectra in proton-proton collisions at sqrts=17.2 GeV are presented. Evidence is shown for the ...existence of a narrow Xi(-)pi(-) baryon resonance with mass of 1.862+/-0.002 GeV/c(2) and width below the detector resolution of about 0.018 GeV/c(2). The significance is estimated to be above 4.2sigma. This state is a candidate for the hypothetical exotic Xi(--)(3/2) baryon with S=-2, I=3 / 2, and a quark content of (dsdsū). At the same mass, a peak is observed in the Xi(-)pi(+) spectrum which is a candidate for the Xi(0)(3/2) member of this isospin quartet with a quark content of (dsus-d). The corresponding antibaryon spectra also show enhancements at the same invariant mass.
The Zimányi-Moszkowski (ZM) Lagrangian describes nuclear matter and stable finite nuclei in the relativistic mean field approximation and even in the non-relativistic limit. It fails, however, to ...predict the correct non-relativistic spin-orbit (SO) coupling. In this paper we improve on this matter by an additional tensor coupling analogous to the one which leads to the anomalous gyromagnetic ratio. It can be adjusted to describe the SO-term without changing the mean field solution of the ZM-Lagrangian for nuclear matter.
Hadron multiplicities are calculated in the framework of the algebraic coalescence rehadronization model (ALCOR), which counts for redistribution of quarks into hadrons for relativistic heavy-ion ...collisions. Dynamical in-medium suppression of the light to heavy quark coalescence factors and the influence of Bjorken flow on the final hadronic composition are incorporated in the model. A comparison is made with the CERN SPS NA35 (S+S) heavy-ion experiment where the total total quark number is fitted to the total charge multiplicity and predictions for NA49 (Pb+Pb) is presented.
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