Studying the Inner Regions of Young Binary Systems using Near-Infrared Interferometry

行星在年轻恒星周围的气体+尘埃盘中形成。一旦行星获得足够的质量，它们就会在盘表面结构中打开缺口，就像在HL Tau等系统中可能观察到的那样。人们已经进行了各种各样的搜索，以探测这些打开缺口的行星本身，但成功有限。因此，假定的间隙开机构的属性需要间接地从观察到的间隙几何推断。重要的下一步是在相互作用物体的性质，特别是它们的质量和轨道是众所周知的情况下研究潮汐相互作用。这样的情况可以在年轻的近距离双星系统中找到，其中一个低质量的恒星伴星在几百天到几年的时间尺度上围绕一个更大质量的中心星星运行。这些伴星可以截断圆盘或打开间隙，探测类似于行星形成的动力学过程。伴星的三维轨道和质量可以用径向速度测量和红外干涉观测来测量。与此同时，潮汐开放间隙的几何形状现在可以在更长的波长上进行测量，例如使用VLTI中红外干涉测量法和阿尔马亚毫米干涉测量法。这个博士项目的目的是用红外/亚毫米干涉测量法研究年轻双星系统的样本，推导出三维轨道，并测量伴星对盘结构施加的潮汐影响。我们将限制基本的恒星和光盘参数，并推导出到伴星星星的吸积率，提供了一个重要的基准模型盘清除和吸积过程中的行星形成盘。

Planets form in the gas+dust discs around young stars. Once the planets have gained sufficient mass they open gaps in the disc surface structure, as might be observed in systems such as HL Tau. Various searches have been conducted in order to detect the gap-opening planets themselves, but with limited success. Therefore, the properties of the putative gap-opening bodies need to be inferred indirectly from the observed gap geometry. The essential next step is to study tidal interactions in cases where the properties of the interacting bodies, in particular their mass and orbit, are well-known. Such cases can be found in young close binary systems, where a low-mass stellar companion orbits a more massive central star on timescales of a few hundred days to a few years. These companions can either truncate the disc or open gaps, probing similar dynamical processes as in planet formation. The 3-D orbits and masses of the companions can be measured using radial velocity measurements and infrared interferometric observations. At the same time, the geometry of the tidally-opened gap can now be measured at longer wavelengths, for instance with VLTI mid-infrared interferometry and ALMA sub-millimetre interferometry.The aim of this PhD project is to study a sample of young binary systems with infrared/sub-millimeter interferometry, to derive 3-D orbits, and to measure the tidal influence that the companions exerts on the disc structure. We will constrain fundamental stellar & disc parameters and derive the accretion rate onto the companion star, providing an important benchmark for modelling disc clearing and accretion processes in planet-forming discs.