标题： 解决未解之谜：使用NESSI搜索低质量盘状宽双星中的未resolved伴星 显示英文标题

标题： Resolving the Unresolved: Using NESSI to Search for Unresolved Companions in Low-mass Disk Wide Binaries

摘要： 由三颗或多颗恒星组成的恒星系统在银河系中并不少见。 近50%的类似太阳的宽距双星（分离距离 >1000天文单位）实际上是高阶多重系统，其中一个分量是一个紧密双星。 此外，高阶多重系统的比例似乎与最宽分量的物理分离距离有关。 这些事实促使了我们目前一些关于最宽广恒星系统如何形成的理论，这些系统可以具有与原恒星核相当甚至更大的分离距离。 然而，目前尚不清楚宽距双星分离距离与高阶多重性之间的相关性是否也适用于低质量双星。 我们展示了针对附近低质量宽距双星正在进行的斑点成像巡天的初步结果。 我们发现样本中整体的高阶多重性比例为$42.0\% \pm 10.9\%$。 如果我们将Gaia显示可能存在伴星的系统包括在内，这个比例增加到$62.0\% \pm 14.2\%$。 这与之前对于大质量恒星和低质量宽距双星的结果一致。 然而，我们没有检测到预期的随分离距离增加的高阶多重性比例上升，这与先前的研究不同。 我们简要探讨了为何低质量恒星中的高阶多重性统计可能有所不同，以及这对宽距双星形成模型的意义可能是什么。 显示英文摘要

摘要： Stellar systems consisting of three or more stars are not an uncommon occurrence in the Galaxy. Nearly 50% of solar-type wide binaries with separations >1000 au are actually higher-order multiples with one component being a close binary. Additionally, the higher-order multiplicity fraction appears to be correlated with the physical separation of the widest component. These facts have motivated some of our current theories behind how the widest stellar systems formed, which can have separations on the order of or larger than protostellar cores. However, it is unclear if the correlation between wide binary separation and higher-order multiplicity extends to low-mass binaries. We present initial results of an ongoing speckle imaging survey of nearby low-mass wide binaries. We find an overall higher-order multiplicity fraction for our sample of $42.0\% \pm 10.9\%$. If we include systems where Gaia indicates that a companion is likely present, this fraction increases to $62.0\% \pm 14.2\%$. This is consistent with previous results from both higher-mass stars and a previous result for low-mass wide binaries. However, we do not detect the expected increase in higher-order multiplicity fraction with separation, as was seen with previous studies. We briefly explore why higher-order multiplicity statistics could be different in low-mass stars, and what the significance might be for models of wide binary formation.