Phenomenological QCD equations of state for neutron star structure and neutron star mergers

主讲人 (Speaker): Toru Kojo（古城徹）副教授

时间 (Time): 星期三, 2017/04/12 - 11:00 to 12:00

地点 (Location): 珠海校区海滨红楼17栋107会议室

摘要 (Abstract):

We discuss cold dense QCD by examining constraints from neutron stars, nuclear experiments, and QCD calculations at low and high baryon density. The two solar mass constraint and suggestive small radii of 10-13 km for canonical neutron stars indicate that the hadron-quark phase transition is crossover or weak first order. Assuming the adiabatic continuity from hadronic to quark matter, we use a schematic quarkmodel for hadron physics and examine the strength of medium coupling constants. We find that to baryon density nb ~ 10n0 (n0: nuclear saturation density), the model coupling should be as large as in the vacuum, indicating that gluons remain non-perturbative even after the quark matter formation.

After studying matter at zero temperature, we move to the equations of state at finite temperature which is important for the supernovae and neutron star mergers. Our quark matter is the color-flavor locked matter with gapped quarks and gluons, and the most relevant thermal contributions come from the Nambu-Goldstone modes. We discuss the properties and compute their contributions to the thermal equations of state.

主讲人简介 (Speaker's CV):

Toru Kojo主要研究的领域为在极端条件下的QCD，包括夸克胶子等离子体，中子星中的致密物质，和强磁场中的QCD。特别对场论中的非微扰问题和多体系统中的涌现现象非常感兴趣，在这方面对低维系统开展过研究。同时利用1/Nc 展开研究了一些核物理中的基本问题。 最近工作主要致力于QCD中的凝聚态问题，瞄准中子星、磁星和超新星的唯像学应用，在不久的将来它们会有更多的观测结果。