CAREER: Probing the Extremes of Star Formation: A Census of Very Low-Mass Stars and Brown Dwarfs in the Local Neighborhood

极低质量（VLM）恒星和褐矮星构成了银河系中最小、最不明亮、但最主要的重子种群之一。它们是恒星形成过程中最小极端的重要探测器，它们的性质告诉我们所有恒星形成和演化的边界条件和变化。然而，尽管vlm无处不在且很重要，但由于其固有的微弱性，vlm的样本在历史上一直很小。PI将为UKIDSS、WISE、2MASS和SDSS全天空巡天观测到的vlm建立一个全面的、交叉匹配的目录。他将测量超过10万个VLM的固有运动，这将是有史以来最大的VLM共固有运动对样本。他还将在4.3米的探索频道望远镜上进行视差项目，以测量距离太阳33秒差距内100多个VLMs的精确距离。这项工作对于解决我们之前在超大质量恒星和超大质量恒星双星编目中的不足是至关重要的，它将为了解低质量和极低质量恒星的形成提供重要的新认识。PI将通过创建波士顿大学（BU）预专业（Pre-MaP）计划，将他的科学使命与多样性努力结合起来。他的项目将通过增加物理科学领域代表性不足的学生数量，直接解决全国对额外STEM专业的需求。波士顿大学Pre-MaP将让一年级学生接触到研究，并将增加天文学和STEM学科的参与度和多样性。

Very low-mass (VLM) stars and brown dwarfs make up the smallest, least luminous, but one of the most dominant baryonic populations of the Milky Way. They are vital probes of the smallest extremes of the star formation process, and their properties inform us about the boundary conditions and variations in the formation and evolution of all stars. However, despite their ubiquity and importance, samples of VLMs have historically been small due to their intrinsic faintness. The PI will build a comprehensive, cross-matched catalog of VLMs that were observed in the UKIDSS, WISE, 2MASS and SDSS all-sky surveys. He will measure proper motions for more than 100,000 VLMs, which will be the largest sample of VLM common-proper motion pairs ever assembled. He will also conduct a parallax program at the 4.3m Discovery Channel Telescope to measure accurate distances to more than 100 VLMs within 33 parsecs of the Sun. This work is essential to address the previous deficiencies in our cataloging of VLMs and VLM binaries, and it will provide a vital new understanding of how low mass and very low-mass stars form.The PI will integrate his science mission with diversity efforts by creating the Boston University (BU) Pre-Majors (Pre-MaP) program. His program will directly address the national need for additional STEM majors by increasing the number of underrepresented students in the physical sciences. BU Pre-MaP will expose first-year underrepresented students to research, and it will increase the participation and diversity in astronomy and STEM disciplines.