通常人们在有限核与核子物质中研究对称能,而本工作利用相对论平均场模型研究包含超子和夸克自由度物质的对称能。发现了含超子和夸克自由度物质中对称能的表观软化,并用相对论模型对此做了阐述。该软化现象提示由重离子碰撞产生的含非核子自由度致密物质的对称能提取将有待细致的甄别。
While the nuclear symmetry energy is usually studied in finite nuclei and nucleonic matter, we study the symmetry energy in relativistic mean-field models with the inclusion of the hyperon and quark degrees of freedom at high densities. Apparent softening of the symmetry energy with the inclusion of hyperon and quark degrees of freedom is found and demonstrated in the relativistic mean-field model. This softening would have associations with the symmetry energy extraction which needs detailed discriminations in dense matter with the admixture of new degrees of freedom created by heavy-ion collisions.