AI 中文总结
本文基于新中子星热演化代码neo-NSCool，研究温度依赖壳层对新中子星冷却的影响，证实热滴中子会减缓早期冷却，含奇异轻物种的壳层物态方程可显著延缓光子冷却时代的冷却。
AI 中文摘要
新中子星（neo-neutron star）阶段是核心坍缩超新星爆发或白矮星吸积诱导坍缩后形成的富热轻子致密天体向冷的去轻子化中子星（NS）演化的中间阶段；若双中子星并合后的最终致密天体未立即坍缩为黑洞，也会经历该阶段。原中子星（proto-NS）演化数值模拟给出的径向温度剖面表明，新中子星阶段初期核心的成分与力学结构近似等同于冷中子星；但外层（即壳层）的成分与力学结构预计会随星体冷却发生变化。Beznogov等人（2020）已研究了具有温度依赖的（内部）包层的新中子星的热演化，本文则探究整个壳层（含其成分）的物态方程（EoS）依赖温度时的情况。我们通过进一步开发并使用中子星热演化代码neo-NSCool，分析新中子星的热、力学与化学演化：首先证实热滴中子会在早期热弛豫阶段略微减缓冷却；随后表明，壳层最深层含奇异轻物种的物态方程，会在光子冷却时代相比重核主导的物态方程显著减缓冷却；壳层成分还会影响结晶过程及冷却时的收缩方式，轻核物态方程会使壳层最内层比重核物态方程保持液态的时间更长。
英文摘要
The neo-neutron star phase is an intermediate stage in the evolution from a hot lepton-rich compact object, which is formed in the aftermath of a core-collapse supernova or an accretion-induced collapse of a white dwarf, to a cold deleptonized neutron star (NS). Alternatively, this phase can occur after a binary NS merger if the final compact object does not collapse immediately into a black hole. Radial temperature profiles provided by numerical simulations of proto-NS evolution suggest that the composition and mechanical structure of the star's core at the beginning of the neo-NS phase are, as a good approximation, identical to those of a cold NS. In contrast, the composition and mechanical structure of the outer layers (i.e., the crust) are expected to change as the star cools. The thermal evolution of neo-NSs with temperature-dependent (inner) envelopes was considered by Beznogov et al. (2020). Here, we investigated what happens if the equation of state (EoS) of the entire crust, including its composition, depends on temperature. We analyzed the thermal, mechanical, and chemical evolution of neo-NSs by further developing and employing neo-NSCool, our NS thermal evolution code. First, we proved that thermally dripped neutrons slightly slow down the cooling during the early thermal relaxation stage. Then, we showed that the EoSs with exotic light species in the deepest layers of the crust result in significantly slower cooling in the photon cooling era compared with the EoSs that favor massive nuclei. The crust's composition also impacts the crystallization process as well as the way in which the crust contracts while it cools. The EoSs with light nuclei cause the innermost layers to remain liquid for a longer time than the EoSs with heavy nuclei.
Comments10 pages, 11 figures, 1 table; submitted to A&A
