Disentangling the Kinematics of the Solar Neighborhood to Calibrate the Ages of Stars and Exoplanets

最近发现的系外行星的爆炸式增长推动了我们对它们多样性的理解的革命，并提出了关于它们形成机制的几个问题。这项研究使我们能够以更全面的视角更好地了解太阳系行星及其演化。随着詹姆斯·韦伯太空望远镜（JWST）即将发射，科学家们正在制定策略，对系外行星的大气进行详细研究，并以化学失衡的形式识别生命的特征。然而，这需要天体物理学界提高我们对恒星特性的理解，这影响了我们对它们系外行星特性的测量，并需要确定一组具有良好校准年龄的系外行星，以测试系外行星形成模型。我开发了专业知识和统计工具，以缓解在太阳附近精确测量恒星年龄的瓶颈。通过确定松散的和同时期的年轻群的恒星成员，可以以无与伦比的精度确定恒星的年龄。我建立了最广泛使用的统计工具来识别太阳附近的年轻协会成员，我用它们来领导多项调查，旨在发现这些年轻协会中失踪的成员，尤其是那些质量较低、最微弱的成员。这使我能够确定许多具有校准年龄的恒星，其中一些是系外行星宿主。这些系统对于精确确定恒星及其系外行星的质量、半径和其他特性非常重要。这些罕见的年龄测量使得用特定年龄的恒星及其系外行星的演化快照来约束恒星演化和行星形成的模型成为可能。我领导的研究揭示了几个具有行星质量的物体，它们不在恒星的轨道上（“行星”）。这些行星很罕见；目前已知的只有十几个，其中有几个是我发现的。然而，一旦它们被发现，它们就为我们提供了年龄校准的行星，与系外行星相比，它们的研究要容易得多，因为我们可以以令人难以置信的精度测量它们的大气特性，而不会因为它们旁边有一颗明亮的主恒星而烦恼。Planemos正成为了解系外行星大气化学和物理结构的重要基准，包括它们的云特性以及它们在数小时和数百万年的时间尺度上是如何演变的。我将建立一个研究生团队，以公平的招聘方式为重点，进一步发现和表征附近的年轻协会和计划，并培养他们掌握先进的数据分析，编码和统计技能。我将培养一种合作和适应的文化，使他们能够充分发挥潜力，成为高素质的人才。这将使他们开始富有成效的职业生涯，并将进一步推动加拿大成为系外行星和恒星天体物理学领域的领导者。

The recent explosion of exoplanet discoveries drove a revolution in our understanding of their variety, and opened several questions about their formation mechanisms. This research is allowing us to better understand solar system planets and their evolution with a more global view. With the imminent launch of the James Webb Space Telescope (JWST), the community is devising strategies to perform detailed studies of exoplanet atmospheres and identify signatures of life in the form of chemical imbalances. This, however, requires the astrophysics community to improve our understanding of stellar properties, which impact our measurements of their exoplanet properties, and to identify sets of exoplanets with a well-calibrated age to test models of exoplanet formation. I developed the expertise and statistical tools to alleviate the bottleneck of measuring accurate stellar ages in the neighborhood of the Sun. It is possible to determine stellar ages with an unequaled precision by identifying stellar members of loose and coeval young associations. I built the most widely used statistical tools to identify young association members near the Sun, and I use them to lead multiple surveys that aim to uncover the missing members of these young associations, especially those with low masses that are faintest. This allowed me to identify many stars with calibrated ages, some of which are exoplanet hosts. These systems are incredibly important to precisely determine the masses, radii and other properties of stars and their exoplanets. These rare age measurements make it possible to constrain models of stellar evolution and planetary formation with snapshots at specific ages over the evolution of stars and their exoplanets. The research that I lead unveiled several objects with planetary masses that are not in orbit around a star ("planemos"). These planemos are rare; only a dozen are currently known, several of which I identified. However, once they are found, they provide us with age-calibrated planemos, significantly easier to study compared with exoplanets, as we can measure their atmosphere properties with an incredible precision without the nuisance of a bright host star immediately next to them. Planemos are becoming important benchmarks to understand the chemical and physical structure of exoplanet atmospheres, including their cloud properties and how they evolve, both over the timescale of hours and millions of years. I will build a team of graduate students with a focus on equitable hiring methods to further the discovery and characterization of nearby young associations and planemos, and train them to acquire advanced skills of data analysis, coding and statistics. I will foster a culture of collaboration and adaptation to allow them to realize their full potential as highly qualified personnel. This will allow them to initiate fruitful careers, and will further Canada as a leader in the fields of exoplanets and stellar astrophysics.