极致密X射线双星演化的研究

Ultracompact X-ray binaries (UCXBs) are usually defined as low-mass X-ray binaries with an orbital period less than one hour, in which the origin of the compact orbit challenges the stellar evolution theory. This project mainly aims at the formation mechanisms of UCXBs. We attempt to investigate the initial parameters space of the progenitors of UCXBs forming by anomalous magnetic braking of Ap/Bp star, and neutron star + helium star binaries evolutionary channel. Meanwhile, comparison between the evolutionary results of the companions and the observational data can constrain the physical models in the stellar and binary evolution. In addition, employing population synthesis we will simulate the numbers and birth-rates of UCXBs in the Galaxy forming by different evolutionary channels.

极致密X射线双星(UCXBs)通常指轨道周期小于1小时的低质量X射线双星，其致密轨道的起源给恒星演化理论提出了挑战。本项目以UCXBs的形成机制为主要研究目标，力图探索通过Ap/Bp星的反常磁制动、中子星+氦星两个演化通道形成UCXBs的前身星系统的初始参数空间，并将伴星的演化结果与观测数据进行对比，以限制恒星和双星演化中的物理模型。此外，我们将利用星族合成方法模拟银河系内不同演化通道形成UCXBs的数目和诞生率。

极致密X射线双星(UCXBs)通常指轨道周期小于1小时的低质量X射线双星，其致密轨道的起源给恒星演化理论提出了挑战。本项目研究了包含Ap/Bp型星的中等质量X射线双星通过反常磁制动来形成致密轨道中等质量脉冲星双星的过程；利用BayeSED，开展了星系能谱分布的统计研究；利用双星星族合成程序，系统计算了超爱丁顿星风模型对应的Ia型超新星的前身星特征分布；研究了超爱丁顿星风模型下，氦物质在碳氧白矮星表面的累积过程。跟踪国际前沿，研究了激变变星中的白矮星质量问题。本项目通过将恒星演化程序的模拟结果和观测数据进行对比，从而限制恒星和双星演化过程中的物理模型，达到了深入理解恒星和双星的演化规律、吸积物理以及高能辐射机制等目的。