发表机构
Hamburger Sternwarte, University of Hamburg; The Oskar Klein Centre, Department of Astronomy, AlbaNova, Stockholm University（汉堡天文台，汉堡大学; 奥斯卡·克莱因中心，天文学系，阿尔巴诺瓦，斯德哥尔摩大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究强子-夸克一阶相变对原中子星演化的影响，发现引力孪星仅在混合星无重子孪星时可能，多数孪星对在高密度相变下被排除。
AI 中文摘要
我们研究从强子物质到退禁闭夸克物质的一阶相变对原中子星演化的影响。为了使我们的结果具有最大适用性，我们构建了一个高度参数化的状态方程，其中我们使用相对论平均场方法模拟强子物质，并使用恒定声速方法模拟夸克物质。我们将原中子星的冷却行为近似为在恒定重子质量下熵递减的序列。某些参数化导致了所谓的“孪星”，即两颗中子星具有相同的（引力）质量但不同的半径。探测它们被视为相变的铁证信号。然而，我们发现原中子星演化表明，引力孪星只有在混合星没有额外的重子孪星时才可能形成。这排除了大多数孪星对，特别是当相变发生在高密度时。在质量-半径图中，未被占据的混合分支似乎处于强子分支的“阴影”之中。
英文摘要
We study the impact of a first-order phase transition from hadronic to deconfined quark matter on the evolution of proto-neutron stars. To maximize the applicability of our results, we construct an equation of state that is highly parameterizable, where we use a relativistic mean field approach to model hadronic matter and a constant speed of sound approach to model quark matter. We approximate the cooling behavior of proto-neutron stars as a sequence of decreasing entropy at constant baryonic mass. Some parameterizations lead to so-called "twin-stars", where two neutron stars have the same (gravitational) mass but different radii. Detecting them is regarded as a smoking gun signal for phase transition. We find, however, that proto-neutron star evolution suggests that gravitational twin stars are only possible if the hybrid star does not have, in addition, a baryonic twin. This rules out most twin star pairs, especially if the phase transition occurs at large densities. In a mass-radius diagram the unpopulated hybrid branch appears to be "in the shadow" of the hadronic branch.
Comments16 pages, 12 figures
