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Phase transitions in isolated strongly interacting systems

M. Veselsky
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Abstract

Thermodynamical properties of the nuclear matter at sub-saturation densities were investigated using a simple van der Waals-like equation of state with an additional term representing the symmetry energy. First-order isospin-asymmetric liquid-gas phase transition appears restricted to isolated isospin-asymmetric systems while the symmetric systems will undergo fragmentation decay resembling the second-order phase transition. The density dependence of the symmetry energy scaling with the Fermi energy satisfactorily describes the symmetry energy at sub-saturation nuclear densities. The deconfinement-confinement phase transition from the quark-gluon plasma to the confined quark matter appears in the isolated systems continuous in energy density while discontinuous in quark density. A transitional state of the confined quark matter has a negative pressure and after hadronization an explosion scenario can take place which can offer explanation for the HBT puzzle as a signature of the phase transition.

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M. Veselsky. 2007-04-26. Phase transitions in isolated strongly interacting systems. https://doi.org/10.1142/s0218301308010866

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