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Thermal QCD Deconfinement Phase Transition in a Finite Volume within the Color-Singletness Condition

M. Ladrem·A. Ait-El-Djoudi·G. Yezza
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Abstract

We study the finite size effects on the thermal deconfinement phase transition from the hadronic gas phase to the QGP phase, using a simple thermodynamic model based on the coexistence of confined and deconfined phases in a finite volume. We first consider the bag model partition function for the QGP, then we include the necessary color singletness condition. By probing the behavior of some physical quantities on the hole range of temperature, it turns out that in a finite size system, all singularities occuring in these quantities in the thermodynamic limit are smoothed out, and the phase transition is then rounded over a broadened critical region, with an additional shifting effect of the critical point induced by the exact color singletness requirement. An analysis of the finite size scaling behavior at criticality of some characteristic quantities allows us to determine the scaling critical exponents characterizing the thermal deconfinement phase transition. The obtained results are in good agreement with those predicted by other studies for a first-order phase transition

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M. Ladrem, A. Ait-El-Djoudi, G. Yezza. 2003-12-31. Thermal QCD Deconfinement Phase Transition in a Finite Volume within the Color-Singletness Condition. https://arxiv.org/abs/hep-ph/0312386

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