论文标题
在HD 169142周围的圆盘上的环形间隙和气体耗尽的腔体中的运动学过量
A kinematic excess in the annular gap and gas depleted cavity in the disc around HD 169142
论文作者
论文摘要
我们在〜8 au空间分辨率下，提出了12CO，13CO和C18O J = 2-1线的ALMA频段6张图像。我们解决了一个中央气体耗尽的腔体，以及两个独立的近对称环状结构在线发射：一个定义明确的内气环[〜25 au]和第二个相对较差的和弥漫性的外气环[〜65 au]。我们在12CO地图中识别局部的超杀伤力特征或垂直流量约为75m/s的垂直流。该特征具有弧形的形状，该弧形跨越约60至45度的PA范围，并且在B1 [26AU]和B2 [59AU]灰尘环之间径向上。通过重建气体表面密度曲线，我们发现压力支持和自重项的背景扰动的大小不足以说明运动学过量。如果是行星起源，气体密度剖面的相对耗竭将表明1 MJ行星。相比之下，中央空腔显示相对光滑的运动学，表明质量伴侣较低和/或具有最小垂直速度分量的二元轨道。
We present ALMA band 6 images of the 12CO, 13CO and C18O J=2-1 line emissions for the circumstellar disc around HD 169142, at ~8 au spatial resolution. We resolve a central gas depleted cavity, along with two independent near-symmetric ring-like structures in line emission: a well-defined inner gas ring [~25 au] and a second relatively fainter and diffuse outer gas ring [~65 au]. We identify a localised super-Keplerian feature or vertical flow with a magnitude of ~75m/s in the 12CO map. This feature has the shape of an arc that spans azimuthally across a PA range of ~60 to 45 degrees and radially in between the B1[26au] and B2[59au] dust rings. Through reconstruction of the gas surface density profile, we find that the magnitude of the background perturbations by the pressure support and self-gravity terms are not significant enough to account for the kinematic excess. If of planetary origin, the relative depletion in the gas-density profile would suggest a 1 Mj planet. In contrast, the central cavity displays relatively smooth kinematics, suggesting either a low mass companion and/or a binary orbit with a minimal vertical velocity component.
