吸积态毫秒 X 射线脉冲星是低质量 X 射线双星的一个重要的子类，在这类源的爆
发态能观测到相干的毫秒 X 射线脉冲。它们具有低质量 X 射线双星和毫秒脉冲星的双
重特证，为毫秒脉冲星的再循环理论提供了直接证据。此外，吸积态毫秒 X 射线脉冲星
对研究致密双星的吸积物理和中子星的物理性质也具有重要意义。然而，它们的形成与
演化仍不清楚。本文利用 MESA 恒星演化程序模拟低质量 X 射线双星演化。基于低质量 X 射线双
星的演化模型和吸积盘不稳定性模型，我们探索吸积态毫秒 X 射线脉冲星的形成与演
化。通过对比我们的结果与吸积态毫秒 X 射线脉冲星的观测特征，我们得到了以下结
论: (1)当物质转移开始时的轨道周期十分靠近分叉周期时，这些低质量 X 射线双星
能再现绝大多数吸积态毫秒 X 射线脉冲星的观测特征。同时，吸积盘的不稳定性模型对
解释绝大多数吸积态毫秒 X 射线脉冲星的形成起到重要作用;(2)具有主序伴星的吸积
态毫秒 X 射线脉冲星最终演化成具有白矮星伴星的吸积态毫秒 X 射线脉冲星;(3)这
些具有主序伴星的吸积态毫秒 X 射线脉冲星更可能具有靠近终龄主序的伴星。
其他摘要
Accreting millisecond X-ray pulsars (AMXPs) are an important subclass of low-mass X-
ray binaries (LMXBs), in which coherent millisecond X-ray pulsations can be observed during
outburst states. They have dual characteristics of LMXBs and millisecond pulsars (MSPs),
providing a direct confirmation for the recycling scenario. Moreover, AMXPs are also important
for the studies of accretion physics of compact binaries and physical properties of neutron stars.
However, their formation and evolution are not well understood.In this thesis, we simulate the evolution of LMXBs with the MESA code. Based on the
binary evolutionary model of LMXBs and the model of accretion disk instability, we explore
the formation and evolution of AMXPs. By comparing our results with the observed properties
of AMXPs, we obtain the following conclusions. (1) Most of the observed AMXPs are likely
produced from LMXBs with orbital periods at the onset of Roche lobe overflow close to the
bifurcation period. Meanwhile, the accretion disk instability may play an important role in
the formation of most AMXPs. (2) The AMXPs with main sequence (MS) donors ultimately
evolve into AMXPs with extremely low-mass He WD donors. (3) Our results indicate that these
AMXPs with MS donors are likely to have donor stars near the terminal-age main sequence.
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