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arXiv · 2009.13487

Phase diagram of alpha matter with Skyrme-like scalar interaction

Leonid M. Satarov·Roman V. Poberezhnyuk·Igor N. Mishustin·Horst Stoecker
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Abstract

The equation of state and phase diagram of strongly interacting matter composed of $α$ particles are studied in the mean-field approximation. The particle interactions are included via a Skyrme-like mean field, containing both attractive and repulsive terms. The model parameters are found by fitting known values of binding energy and baryon density in the ground state of $α$ matter, obtained from microscopic calculations by Clark and Wang. Thermodynamic quantities of $α$ matter are calculated in the broad domains of temperature and baryon density, which can be reached in heavy-ion collisions at intermediate energies. The model predicts both first-order liquid-gas phase transition and Bose-Einstein condensation of $α$ particles. We present the profiles of scaled variance, sound velocity and isochoric heat capacity along the isentropic trajectories of $α$ matter. Strong density fluctuations are predicted in the vicinity of the critical point at temperature $T_c\approx 14~\textrm{MeV}$ and density $n_c\approx 0.012~\textrm{fm}^{-3}$.

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Leonid M. Satarov, Roman V. Poberezhnyuk, Igor N. Mishustin, Horst Stoecker. 2021-02-07. Phase diagram of alpha matter with Skyrme-like scalar interaction. https://doi.org/10.1103/physrevc.103.024301

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