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arXiv · 2410.21746

Probing nuclear liquid-gas phase transition with isospin correlations

Michał Marczenko·Krzysztof Redlich·Chihiro Sasaki
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Abstract

We investigate the fluctuations of the net-baryon number near the critical point of the liquid-gas phase transition. We use the parity doublet model in the mean-field approximation fixed to the zero-temperature properties of nuclear matter to account for critical behavior. We explicitly calculate the fluctuations of the net-proton and net-neutron numbers as well as their correlations in the isospin-symmetric matter. We focus on the qualitative properties and systematics of the first- to fourth-order susceptibilities and their ratios. We demonstrate that the fluctuations of net-proton number do not reflect the total net-baryon number fluctuations in the vicinity of the nuclear liquid-gas phase transition. We also study the behavior of the baryon and proton number factorial cumulants. We highlight the importance of the non-trivial correlations between protons and neutrons.

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Michał Marczenko, Krzysztof Redlich, Chihiro Sasaki. 2024-10-29. Probing nuclear liquid-gas phase transition with isospin correlations. https://doi.org/10.1103/4ccc-j338

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