时间： 11月30日（周四） 下午 13：30

地点： 勤园20-518

报告摘要：

We investigate the properties of quark nuggets and quark stars, where an equivparticle model is adopted with both the linear confinement and leading-order perturbative interactions accounted for using density-dependent quark masses. The energy, free energy, entropy, charge-to-mass ratio, strangeness per baryon, and root-mean-square radius of $\beta$-stable strangelets and udQM nuggets are obtained with various parameter sets. The effects of quark matter symmetry energy are examined, where udQM nuggets at A ≈ 1000 can be more stable than others if large symmetry energy is adopted. In such cases, larger udQM nuggets will decay via fission and the surface of a udQM star will fragment into a crust made of udQM nuggets and electrons. The shell effects are examined by solving the Dirac equations for quarks in the mean-field approximation, which diminish with temperature as the occupation probability of each single-particle levels fixed by the Fermi-Dirac statistics, i.e., shell dampening. Consequently, instead of decreasing with temperature, the surface tension extracted from a liquid-drop formula increases with $T$ until reaching its peak at $T\approx 20$-40 MeV with vanishing shell corrections, where the formula roughly reproduces the free energy per baryon of all strangelets. The curvature term, nevertheless, decreases with $T$ despite the presence of shell effects. The neutron and proton emission rates are fixed microscopically according to the external nucleon gas densities that are in equilibrium with strangelets, which generally increase with $T$ ($\lesssim 50$ MeV) for stable strangelets but decrease for those that are unstable against nucleon emission at $T=0$.

报告人简介：

夏铖君2008年于浙江工业大学获学士学位；2011年于北京工业大学获硕士学位；2014年于中国科学院大学获博士学位。2014年-2016年在中国科学院理论物理研究所从事博士后研究；2016年-2022年在浙江大学宁波理工学院工作；2022年起在扬州大学工作。在国内外本领域高水平期刊上发表论文60多篇，主持一项国家自然科学基金，参加一项科技部平方公里阵列射电望远镜(SKA)专项科学预研项目。夏铖君主要从事夸克物质、重子物质、及夸克-强子混合物质的研究，应用各类理论及模型工具对致密星、夸克物质团、超核等奇特物质进行了大量研究，对高密物质的各类非均匀结构及夸克-真空 / 强子界面效应有了一些理解，并在国内和国际会议上受邀报告多次。