论文标题
Gaia DR3三元组的奥秘：近亲二进制的广泛怪物的发生率，方向和怪异
The mystery in Gaia DR3 triples: occurrence rates, orientations, and eccentricities of wide tertiaries around close binaries
论文作者
论文摘要
几十年来，近亲的形成一直是一个悬而未决的问题。三重系统中有很大一部分的紧密二进制文件，表明它们的形成可能与Kozai-Lidov机制有关。但是，这张照片仍在争论中，因为许多观察到的三元组的配置不太可能触发Kozai-Lidov机制。在本文中，我们使用盖亚数据释放3的近距离二进制样本，包括黯然失色，光谱和天文二进制文件，研究内部二进制文件与其广泛的怪胎之间的神秘联系。我们表明，随着内部二进制文件的减小，宽三纪（$ 10^3 $ - $ 10^4 $ au）的分数增加。远程二进制文件的大三级分数（中位轨道周期为$ 0.41美元）的价格为$ 2.33 \ pm0.11 $倍，比田间二进制二进制分数高。此外，$ \ sim10^4 $ au的暂定过剩，用于剥落二进制文件。使用$ v $ - $ r $角度分布，我们表明广泛的三室具有相对于内部二进制的各向同性方向，并且可以排除共同计划轨道。宽三角的推断偏心分布是一致的（$ <1σ$），而热（$ f（e）\ propto e $）类似于类似的分离的宽二进制文件。动态展开场景是不受欢迎的，因为它可以预测高度怪异的宽轨道，这与我们的发现不一致。为了使Kozai-Lidov机制在$> 10^3 $ au的情况下对宽开头有效，内部二进制文件的初始分离必须为$> 3 $ au。需要对未来的理论研究来探索这些大初始分离和大三级分离的参数空间。
The formation of close binaries has been an open question for decades. A large fraction of close binaries are in triple systems, suggesting that their formation may be associated with the Kozai-Lidov mechanism. However, this picture remains under debate because the configurations of many observed triples are unlikely to trigger the Kozai-Lidov mechanism. In this paper, we use the close binary samples, including eclipsing, spectroscopic, and astrometric binaries, from Gaia Data Release 3 to investigate the mysterious connection between inner binaries and their wide tertiaries. We show that the wide tertiary (at $10^3$-$10^4$ AU) fraction increases with decreasing orbital periods of the inner binaries. The wide tertiary fraction of eclipsing binaries (a median orbital period of $0.41$ day) is $2.33\pm0.11$ times higher than the field wide binary fraction. Furthermore, there is a tentative excess at $\sim10^4$ AU for tertiaries of eclipsing binaries. Using the $v$-$r$ angle distributions, we show that wide tertiaries have isotropic orientations with respect to the inner binaries, and the co-planar orbits can be ruled out. The inferred eccentricity distribution of wide tertiaries is consistent ($<1σ$) with being thermal ($f(e)\propto e$), similar to wide binaries at similar separations. The dynamical unfolding scenario is disfavored because it predicts highly eccentric wide tertiaries, which is inconsistent with our findings. For the Kozai-Lidov mechanism to be effective for wide tertiaries at $>10^3$ AU, the initial separations of the inner binaries need to be $>3$ AU. Future theoretical investigations are needed to explore the parameter space at these large initial separations and large tertiary separations.
