arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1603.09352astro-ph.EP
收藏

最近原行星盘中1 AU处的环状子结构和间隙

Ringed Substructure and a Gap at 1 AU in the Nearest Protoplanetary Disk

Sean M. Andrews, David J. Wilner, Zhaohuan Zhu, Tilman Birnstiel, John M. Carpenter, Laura M. Perez, Xue-Ning Bai, Karin I. Oberg, A. Meredith Hughes, Andrea Isella, Luca Ricci

摘要:

我们目前的长基线阿塔卡马大型毫米/亚毫米阵列(ALMA)的870微米的连续发射从最近的富含气体的原行星盘,TW Hya周围,跟踪毫米大小的粒子到小至1 AU(20 mas)的空间尺度的观测。这些数据揭示了一系列同心环形子结构,其形式为亮区和窄暗环(1-6 AU),对比度适中(5-30%)。我们将这些特征与固体的浓度相关联,这些固体的向内径向漂移减慢或停止,大概是在当地的气体压力最大值。未检测到明显的非轴对称结构。一些观察到的功能发生在附近的温度,可能与冷凝前的主要挥发性物质,但相对较小的亮度对比度也可能是磁化盘演变(所谓的纬向流)的结果。其他特征,特别是距离恒星仅1 AU的狭窄黑暗环,可能表明盘和年轻行星之间的相互作用。这些数据表明,在~AU尺度上有序的子结构可能是盘演化中常见的基本因素,并且高分辨率微波成像可以帮助描述它们在行星形成时期的特征。

英文摘要:

We present long-baseline Atacama Large Millimeter/submillimeter Array (ALMA) observations of the 870 micron continuum emission from the nearest gas-rich protoplanetary disk, around TW Hya, that trace millimeter-sized particles down to spatial scales as small as 1 AU (20 mas). These data reveal a series of concentric ring-shaped substructures in the form of bright zones and narrow dark annuli (1-6 AU) with modest contrasts (5-30%). We associate these features with concentrations of solids that have had their inward radial drift slowed or stopped, presumably at local gas pressure maxima. No significant non-axisymmetric structures are detected. Some of the observed features occur near temperatures that may be associated with the condensation fronts of major volatile species, but the relatively small brightness contrasts may also be a consequence of magnetized disk evolution (the so-called zonal flows). Other features, particularly a narrow dark annulus located only 1 AU from the star, could indicate interactions between the disk and young planets. These data signal that ordered substructures on ~AU scales can be common, fundamental factors in disk evolution, and that high resolution microwave imaging can help characterize them during the epoch of planet formation.

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。

↑