Exploring the Effect of Planet-Disk Interaction on Exoplanetary Atmospheres

探索行星盘相互作用对系外行星大气的影响

• 批准号: 577027-2022
• 负责人: Lee, EveEJ
• 金额: $ 3.28万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Alliance Grants
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=762302
• 关键词: Exploring; Effect; Planet; Disk; Interaction

Compositions of exoplanetary atmospheres encode the planet's formation history. Within a spinning disk of gas and dust that surround a young star, the dust grains coagulate into rocks as massive as a few Earth masses and these massive rocks build atmospheres by gravitationally attracting the surrounding gas. The chemical composition of both the grains and the gas is expected to change drastically with location, depending on the structure of the disk. Characterizing the elemental ratio of planets can inform where in the disk the planet has assembled. Such inference requires solid understanding of the varying elemental abundance in both solid and gaseous form at different locations of a disk. The current state-of-the-art is to compute the location of phase transitions of several volatile species such as water and carbonaceous oxides by evolving the underlying disk, independent of the planets that form within them. However, planets are known to perturb the disk significantly carving out gaps and establishing traps of dust grains, interior to which the gas may be more pristine than previously thought. We propose to quantify the effect of planet-disk interactions on the exoplanetary atmospheres. In particular, through a combination of numerical hydrodynamic calculations using an open-source code ATHENA++ and semi-analytic models, we aim to 1) determine the efficiency at which the dust grains of varying sizes could be trapped by planet-driven pressure bumps; 2) track the coagulation of these trapped dust into secondary planets thereby investigating the effect of multi-planetary dynamics in setting the disk composition; 3) translate the trajectory of grains in these perturbed disks into chemical evolution of volatiles and refractory species; and to 4) build a model that evolves in time the degree of post-formation pollution in the upper atmospheres of planets. Using these insights, we will fill in the current knowledge gap connecting the evolution of protoplanetary disks as they are perturbed by the planets that emerge within them with the observable trends in studies of exoplanetary atmospheres that can be tested with the new James Webb Space Telescope and the upcoming space mission Ariel.

系外星氛围的组成编码地球的形成历史。在围绕年轻恒星的气体和灰尘的旋转盘中，尘土谷物凝结成像几个地球质量一样大的岩石，这些巨大的岩石通过重力吸引周围的气体来营造气氛。谷物和气体的化学成分预计会随着磁盘的结构而发生巨大变化。表征行星的元素比例可以告知行星在磁盘中组装的位置。这种推论需要在磁盘的不同位置的固体和气态形式中对不同元素丰度的扎实理解。当前的最新目前是通过进化下面的磁盘来计算几种挥发性物种（例如水和碳氧化）的相变位置，而与它们内部形成的行星无关。然而，已知行星会扰动磁盘可显着弥补缝隙并建立尘埃陷阱，内部的气体可能比以前想象的要更原始。我们建议量化行星 - 磁盘相互作用对超球星大气的影响。特别是，通过使用开源代码Athena ++和半分析模型的数值流体动力计算结合，我们的目的是1）确定可以通过行星驱动的压力凸起捕获变化尺寸的粉尘粒的效率； 2）跟踪这些被困的灰尘凝结成二级行星，从而研究了多个星际动力学在设置磁盘组合物中的影响； 3）将这些扰动磁盘中谷物的轨迹转化为挥发物和难治物种的化学演化； 4）建立一个随着时间的流逝发展的模型，该模型在行星上层大气中的形成后污染程度。使用这些洞察力，我们将填补当前的知识差距，以连接原球门磁盘的演变，因为它们在其中出现的行星扰动了它们，而这些磁盘会与可观察到的巨大气氛研究的可观察到的趋势，这些趋势可以与新的James Webb太空望远镜和即将到来的太空宣布Ariel一起测试。