Phase diagram of alpha matter with Skyrme-like scalar interaction

TL;DR

This paper models the phase diagram of alpha matter using a Skyrme-like mean-field approach, predicting phase transitions, critical points, and thermodynamic properties relevant to heavy-ion collision experiments.

Contribution

It introduces a Skyrme-like mean-field model fitted to microscopic data to study the phase diagram and thermodynamics of alpha matter, including phase transitions and critical phenomena.

Findings

Prediction of first-order liquid-gas phase transition.

Identification of Bose-Einstein condensation of alpha particles.

Locating the critical point at T_c≈14 MeV and n_c≈0.012 fm^{-3}.

Abstract

The equation of state and phase diagram of strongly interacting matter composed of $\alpha$ 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 $\alpha$ matter, obtained from microscopic calculations by Clark and Wang. Thermodynamic quantities of $\alpha$ 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 $\alpha$ particles. We present the profiles of scaled variance, sound velocity and isochoric heat capacity along the isentropic trajectories of $\alpha$ matter. Strong density fluctuations are predicted in the vicinity of the critical point at temperature $T_c\approx 14~\textrm{MeV}$ and density $n_c\approx 0.012~\textrm{fm}^{-3}$.