Speed of sound and liquidgas phase transition in nuclear matter
Abstract
We investigate the speed of sound in nuclear matter at finite temperature and density (chemical potential) in the nonlinear Walecka model. The numerical results suggest that the behaviors of sound speed are closely related to the the nuclear liquidgas (LG) phase transition and the associated spinodal structure. The adiabatic sound speed is nonzero at the critical endpoint (CEP) in the meanfield approximation. We further derive the boundary of vanishing sound velocity in the temperaturedensity phase diagram, and point out the region where the sound wave equation is broken. The distinction between the speed of sound in nuclear matter and that in quark matter contains important information about the equation of state of strongly interacting matter at intermediate and high density. We also formulate the relations between differently defined speeds of sound using the fundamental thermodynamic relations.
 Publication:

Physical Review C
 Pub Date:
 January 2023
 DOI:
 10.1103/PhysRevC.107.014903
 arXiv:
 arXiv:2212.08263
 Bibcode:
 2023PhRvC.107a4903H
 Keywords:

 Nuclear Theory;
 High Energy Physics  Phenomenology
 EPrint:
 11pages, 16 figures