Probing protoplanetary disk evolution in the Chamaeleon II region
Probing protoplanetary disk evolution in the Chamaeleon II region
复制标题
探测 Chamaeleon II 区域的原行星盘演化
DOI：
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发表时间：
2021
影响因子：
6.5
通讯作者：
M. Schreiber
中科院分区：
文献类型：
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作者：
M. Villenave;F. Ménard;W. Dent;M. Benisty;G. V. D. Plas;J. Williams;M. Ansdell;Á. Ribas;C. Caceres;H. Cánovas;L. Cieza;A. Hales;I. Kamp;C. Pinte;D. Principe;M. Schreiber
上下文。刻画原行星盘的演化对于提高我们对行星形成的理解是必要的。需要对尘埃和气体进行约束，以确定主要的圆盘消散机制。目标。我们的目标是将Chamaeleon II(CHA II)恒星形成区的盘状尘埃质量与其他年龄在1到10 Myr之间的区域进行比较。方法：研究方法。我们使用ALMA波段6(1.3 mm)观测了CHA II中的29个原行星盘。尘埃质量的估算是从连续谱数据得出的。结果。在我们最初的29个磁盘样本中，我们在连续统中检测到22个源，在12CO中检测到10个源，在13CO中检测到3个源，在C18O(J=2−1)中没有检测到源。此外，我们在连续谱和12CO发射中检测到两个伴星。假设来自光学薄尘埃的热发射，大多数磁盘尘埃质量低于10M⊕。包括未探测到的尘埃，我们从生存分析中得出尘埃质量的中位数为4.5±1.5M⊕。我们将CHA II中盘尘埃质量和盘星质量比的一致估计与其他6个年龄范围为1-10 Myr的低质量孤立恒星形成区进行了比较：上Sco、CRA、IC348、Cha I、狼疮和金牛座。当比较尘埃与恒星的质量比时，我们发现Cha II中的圆盘质量与上Sco和金牛座的质量有统计上的不同，我们确认了样本中最古老的区域上Sco的圆盘在统计上比所有其他区域的质量要小。对来自相似质量仓的尘埃质量分布进行第二次统计检验，我们发现这些区域与CHA II没有统计差异。我们最简单地将这些趋势解释为磁盘尘埃质量随时间或尘埃演化而下降的迹象。恒星形成区域中不同的全球初始条件也可能起到一定作用，但它们对盘群性质的影响很难在缺乏附近大质量恒星的恒星形成区域中分离出来。
Context. Characterizing the evolution of protoplanetary disks is necessary to improve our understanding of planet formation. Constraints on both dust and gas are needed to determine the dominant disk dissipation mechanisms. Aims. We aim to compare the disk dust masses in the Chamaeleon II (Cha II) star-forming region with other regions with ages between 1 and 10 Myr. Methods. We use ALMA band 6 observations (1.3 mm) to survey 29 protoplanetary disks in Cha II. Dust mass estimates are derived from the continuum data. Results. Out of our initial sample of 29 disks, we detect 22 sources in the continuum, 10 in 12CO, 3 in 13CO, and none in C18O (J = 2−1). Additionally, we detect two companion candidates in the continuum and 12CO emission. Most disk dust masses are lower than 10 M⊕, assuming thermal emission from optically thin dust. Including non-detections, we derive a median dust mass of 4.5± 1.5 M⊕ from survival analysis. We compare consistent estimations of the distributions of the disk dust mass and the disk-tostellar mass ratios in Cha II with six other low mass and isolated star-forming regions in the age range of 1–10 Myr: Upper Sco, CrA, IC 348, Cha I, Lupus, and Taurus. When comparing the dust-to-stellar mass ratio, we find that the masses of disks in Cha II are statistically different from those in Upper Sco and Taurus, and we confirm that disks in Upper Sco, the oldest region of the sample, are statistically less massive than in all other regions. Performing a second statistical test of the dust mass distributions from similar mass bins, we find no statistical differences between these regions and Cha II. Conclusions. We interpret these trends, most simply, as a sign of decline in the disk dust masses with time or dust evolution. Different global initial conditions in star-forming regions may also play a role, but their impact on the properties of a disk population is difficult to isolate in star-forming regions lacking nearby massive stars.