arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 2311.06332astro-ph.SRastro-ph.HE
收藏

从三维到一维:一种处理公共包层演化的一维方法

Going from 3D to 1D: A one-dimensional approach to common-envelope evolution

V. A. Bronner, F. R. N. Schneider, Ph. Podsiadlowski, F. K. Roepke

AI总结:

本文提出一种基于MESA的一维公共包层演化模型,通过参数化阻力与轨道能量加热模拟螺旋内过程,并与三维模拟对比验证,发现复合能对包层抛射至关重要。

摘要:

公共包层(CE)阶段是双星演化的关键阶段,因为在此阶段轨道间距可能急剧缩小,同时抛射出巨星的外层包层。对公共包层演化进行三维(3D)流体动力学模拟对于理解该阶段所涉及的机制不可或缺。尽管这些模拟提供了重要见解,但计算成本高昂。我们提出了一种一维(1D)模型,在恒星演化代码MESA中模拟公共包层阶段,采用参数化阻力公式描述动力学阻力,并将释放的轨道能量作为热量添加到包层中。我们计算了一颗0.97太阳质量的渐近巨分支星与质量比分别为0.25、0.50和0.75的点质量伴星的公共包层事件,并将其与相同设置的3D模拟进行比较。该1D公共包层模型包含两个自由参数,我们证明了这两个参数对于使1D方法的螺旋内行为和被抛射包层质量比例与3D模拟相匹配都是必需的。对于质量比为0.25和0.50的情况,我们找到了拟合良好的1D模拟;而对于质量比为0.75的情况,由于1D方法中的某些假设不再有效,我们未能找到与3D模拟令人满意的拟合。在所有模拟中,我们发现释放的复合能对于加速包层并驱动其抛射至关重要。

英文摘要:

The common-envelope (CE) phase is a crucial stage in binary star evolution because the orbital separation can shrink drastically while ejecting the envelope of a giant star. Three-dimensional (3D) hydrodynamic simulations of CE evolution are indispensable to learning about the mechanisms that play a role during the CE phase. While these simulations offer great insight, they are computationally expensive. We propose a one-dimensional (1D) model to simulate the CE phase within the stellar evolution code $\texttt{MESA}$ by using a parametric drag force prescription for dynamical drag and adding the released orbital energy as heat into the envelope. We compute CE events of a $0.97\,\mathrm{M}_\odot$ asymptotic giant-branch star and a point mass companion with mass ratios of 0.25, 0.50, and 0.75, and compare them to 3D simulations of the same setup. The 1D CE model contains two free parameters, which we demonstrate are both needed to fit the spiral-in behavior and the fraction of ejected envelope mass of the 1D method to the 3D simulations. For mass ratios of 0.25 and 0.50, we find good-fitting 1D simulations, while for a mass ratio of 0.75, we do not find a satisfactory fit to the 3D simulation as some of the assumptions in the 1D method are no longer valid. In all our simulations, we find that the released recombination energy is important to accelerate the envelope and drive the ejection.

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。

↑