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arXiv 1202.4901astro-ph.HEgr-qc
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双紧对象I:公共包络对合并率的意义

Double Compact Objects I: The Significance Of The Common Envelope On Merger Rates

Michal Dominik, Krzysztof Belczynski, Christopher Fryer, Daniel Holz, Emanuele Berti, Tomasz Bulik, Ilya Mandel, Richard O'Shaughnessy

摘要:

恒星和双星演化的观测和理论发展的最后十年提供了一个机会,将重大改进的预测人口合成模型。我们用StarTrack程序计算了NS-NS、BH-NS和BH-BH合并的星系合并率。最重要的修订包括:更新的风质量损失率(允许恒星质量的黑洞达到$80 \msun$),一个现实的处理共同的信封阶段(一个过程,可以影响合并率2- 3个数量级),和一个新的质量中子星/黑洞质量分布(与观察到的“质量差距”一致)。我们的发现包括:(i)包络的结合能在决定双星是否在哈勃时间内合并方面起着关键作用。(ii)我们的描述出生踢从超新星起着重要的作用,特别是BH-BH系统的形成。(iii)BH-BH系统的质量可以在低金属丰度或弱风的情况下大幅增加。(iv)某些参数组合低估了银河系NS-NS合并率,可以排除。{ \em(v)}根据我们以前的工作,包含延迟超新星的模型与观测到的NS/BH“质量间隙”不一致。这是一系列三篇论文中的第一篇。第二篇论文将研究作为红移、恒星形成率和金属丰度函数的双致密天体的合并率。在第三篇论文中,我们将介绍引力波观测站的探测率,使用最新的信号波形和灵敏度曲线。

英文摘要:

The last decade of observational and theoretical developments in stellar and binary evolution provides an opportunity to incorporate major improvements to the predictions from populations synthesis models. We compute the Galactic merger rates for NS-NS, BH-NS, and BH-BH mergers with the StarTrack code. The most important revisions include: updated wind mass loss rates (allowing for stellar mass black holes up to $80 \msun$), a realistic treatment of the common envelope phase (a process that can affect merger rates by 2--3 orders of magnitude), and a qualitatively new neutron star/black hole mass distribution (consistent with the observed "mass gap"). Our findings include: (i) The binding energy of the envelope plays a pivotal role in determining whether a binary merges within a Hubble time. (ii) Our description of natal kicks from supernovae plays an important role, especially for the formation of BH-BH systems. (iii) The masses of BH-BH systems can be substantially increased in the case of low metallicities or weak winds. (iv) Certain combinations of parameters underpredict the Galactic NS-NS merger rate, and can be ruled out. {\em (v)} Models incorporating delayed supernovae do not agree with the observed NS/BH "mass gap", in accordance with our previous work. This is the first in a series of three papers. The second paper will study the merger rates of double compact objects as a function of redshift, star formation rate, and metallicity. In the third paper we will present the detection rates for gravitational wave observatories, using up-to-date signal waveforms and sensitivity curves.

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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