论文标题
低积聚者的普查。我:目录
A Census of the Low Accretors. I: The Catalog
论文作者
论文摘要
观察结果表明,磁盘频率和积聚前序列恒星的比例随着人口的年龄的增长而减小,并且有些恒星似乎有圆盘,而它们的积聚停止了。尽管如此,目前尚不清楚带有磁盘的恒星如何阻止其积聚。为了洞悉低质量年轻恒星中积聚的最后阶段,我们对含盘恒星进行了调查,这些恒星被认为是非精神分子,以鉴定恒星仍然以非常低的速率吸收。在这里,我们介绍了Chamaeleon I,Orion OB1,Upper Scorpius,$γ$ Velorum和Upper Centaurus Lupus在Chamaeleon I,Orion OB1,上ob1,$ 10830作为敏感探测器的敏感探测器中对170个含磁盘非核心星的调查的第一个目录。我们将行概况分类为六种类型,并认为那些显示红移和/或蓝光吸收的人仍在积聚。使用这些分类,我们发现,在先前被归类为非囊肿的含盘的恒星中,至少20-30%仍在吸收,其中年轻人年龄的人数较大。尽管外磁盘签名和积聚状态之间的差异尚不清楚,但我们发现内磁盘过剩状态和积聚状态之间存在差异。新鉴定的增生器的质量不偏爱,这表明抑制积聚的过程并不直接取决于典型的T牛tauri恒星质量范围。最后,我们发现,在低积压水平下,在10%高度标准下的H $α$宽度误解了比线等效宽度更大的增生器。
Observations have shown that the disk frequency and the fraction of accreting pre-main-sequence stars decrease with the age of the population and that some stars appear to have disks while their accretion has stopped. Still, it is unclear how disk-bearing stars stop their accretion. To provide insight into the last stages of accretion in low-mass young stars, we conducted a survey of disk-bearing stars that are thought to be non-accretors to identify stars still accreting at very low rates. Here we present the first catalog of the survey of 170 disk-bearing non-accreting stars in Chamaeleon I, Orion OB1, Upper Scorpius, $γ$ Velorum, and Upper Centaurus Lupus, using He I $λ$10830 as a sensitive probe of accretion. We classify the line profiles into six types and argue that those showing redshifted and/or blueshifted absorption are still accreting. Using these classifications, we found that, among disk-bearing stars previously classified as non-accretors, at least 20-30% are still accreting, with a larger fraction of those at younger population ages. While the difference between the outer disk signature and accretion status is unclear, we find a difference between the inner disk excess and accretion status. There is no preference in the mass of the newly identified accretors, suggesting that the processes inhibiting accretion do not directly depend on mass in the typical mass range of T Tauri stars. Lastly, we found that at a low accretion level, the H$α$ width at the 10% height criteria mischaracterizes a larger fraction of accretors than the line's equivalent width.