发表机构
SETI Institute; School of Physics, UNSW Science; Alfred University; University of Hawai’i at Mānoa; University of Vienna; John Hopkins University; NASA Jet Propulsion Laboratory, California Institute of Technology; University of Southern Queensland; European Southern Observatory（SETI研究所; 新南威尔士大学理学院物理系; 阿尔弗雷德大学; 夏威夷大学马诺阿分校; 维也纳大学; 约翰霍普金斯大学; 加州理工学院NASA喷气推进实验室; 昆士兰科技大学; 欧洲南方天文台）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究提出基于多波段时域巡天吸积激波辐射色依赖性的新方法，测量年轻恒星内盘截断半径，将应用于NASA的EVE任务，助力检验角动量演化理论并揭示内盘对早期行星结构的影响。
AI 中文摘要
内盘截断半径$R_T$在恒星-盘相互作用及恒星-盘-行星系统的早期演化中发挥关键作用，但观测上测量该参数颇具挑战性。我们提出一种确定年轻吸积系统中$R_T$的新方法，该方法基于多波段时域巡天中吸积激波辐射的色依赖性。基于Robinson等人（2017,2021）的吸积模拟，我们生成近紫外和光学波段的合成色-星等图，以预测吸积恒星随$R_T$变化的位置。我们对拥有干涉测量$R_T$估计值的年轻恒星测试这些模型预测，发现结果吻合度极高。我们将该新技术应用于金牛座和上天蝎座26颗经典T Tauri星的试点巡天，发现多数源的截断半径较小，$R_T < 4\thinspace R_\bigstar$，且$R_T$的整体分布与干涉测量推断的分布在统计上相似，但与发射线建模推断的分布不同。最后，我们讨论该技术在NASA任务概念EVE中的应用，目标是对银河系内数百颗年轻恒星同时测量内盘截断半径、共转半径和质量吸积率。该任务将开展的内盘特性前所未有的巡天，将首次对年轻恒星的角动量演化理论进行严格检验，并揭示内盘条件对早期行星结构的影响。
英文摘要
The inner disk truncation radius, $R_T$, plays a crucial role in the regulation of star-disk interaction and the early evolution of star-disk-planet systems; however, measuring this parameter is observationally challenging. We present a new method for determining $R_T$ in young accreting systems that hinges on the color dependence of the accretion shock emission in multi-band time-domain surveys. Based on the accretion simulations of Robinson et al. (2017, 2021), we produce synthetic color-magnitude diagrams at near-UV and optical wavelengths that predict the loci of accreting stars as a function of $R_T$. We test these model predictions on young stars with interferometric $R_T$ estimates, finding very good agreement in our results. We apply this novel technique to a pilot survey of 26 classical T Tauri stars in Taurus and Upper Scorpius. We find a predominance of sources with small truncation radii, $R_T < 4\ R_\star$, and an overall distribution of $R_T$ that is statistically similar to that inferred from interferometric studies, while differing from those inferred from emission line modeling. Finally, we discuss the application of this technique to NASA's mission concept EVE, with the goal to provide simultaneous measurements of inner disk truncation radii, corotation radii and mass accretion rates for hundreds of young stars across the Galaxy. The unprecedented survey of inner disk properties that the mission would produce would enable the first stringent test of angular momentum evolution theories in young stars and reveal the impact of the inner disk conditions on early planet architectures.
Comments20 pages, 6 figures, 2 tables; submitted to AAS Journals with slight text reorganization and figure edits
