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arXiv 1808.05992astro-ph.SRastro-ph.HE
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吸积诱导坍缩事件的单简并模型

The single-degenerate model for the progenitors of accretion-induced collapse events

Bo Wang

摘要:

氧氖白矮星(ONe WD)的吸积诱导坍缩(AIC)是恒星演化的一种理论预测结果,可能与某些中子星系统的形成有关。然而,AIC事件的起源模型还没有得到很好的研究,最近的研究表明,当CO WD表面发生偏离中心的碳点火时,CO WD+He星系统也可能通过AIC过程参与中子星系统的形成。本文系统地研究了AIC事件的单简并(SD)模型,包括CO WD+He星通道和ONe WD+MS/RG/He星通道的贡献。首先,在详细的双星演化计算的基础上,给出了在轨道周期--次质量平面内产生AIC事件的这些SD通道的初始参数空间。然后,根据一种二进制总体综合方法,基于初始参数空间,给出了这些SD通道的AIC事件发生率和延迟时间。我发现我们银河系中AIC事件的发生率在$\sim0.3-0.9\times10^{-3}$ \,yr $^{-1}$的范围内,它们的延迟时间为$>$ 30\,Myr。研究还发现,ONe WD+He星通道是产生AIC事件的主要途径,而CO WD+He星通道在研究AIC事件的起源时不可忽略。

英文摘要:

It has been suggested that the accretion-induced collapse (AIC) of an oxygen-neon white dwarf (ONe WD) to a neutron star is a theoretically predicted outcome in stellar evolution, likely relating to the formation of some neutron star systems. However, the progenitor models of AIC events are still not well studied, and recent studies indicated that CO WD+He star systems may also contribute to the formation of neutron star systems through AIC process when off-centre carbon ignition happens on the surface of the CO WD. In this work, I studied the single-degenerate (SD) model of AIC events in a systematic way, including the contribution of the CO WD+He star channel and the ONe WD+MS/RG/He star channels. Firstly, I gave the initial parameter space of these SD channels for producing AIC events in the orbital period--secondary mass plane based on detailed binary evolution computations. Then, according to a binary population synthesis approach, I gave the rates and delay times of AIC events for these SD channels based on their initial parameter space. I found that the rates of AIC events in our galaxy are in the range of $\sim0.3-0.9\times10^{-3}$\,yr$^{-1}$,and that their delay times are $>$30\,Myr. I also found that the ONe WD+He star channel is the main way to produce AIC events, and that the CO WD+He star channel cannot be ignored when studying the progenitors of AIC events.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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