Peering at the First Stages of Planet Formation: Getting a Clearer View of Grain Growth, Settling, and Clearing in Dusty Disks

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。Catherine Espaillat被授予美国国家科学基金会天文学和天体物理学博士后奖学金，在哈佛-史密森天体物理学中心开展研究和教育项目。埃斯帕拉特博士将量化低质量前主序星（太阳的前身）周围原行星盘中尘埃的演化。为此，PI将在金牛座、变色龙和蛇夫座的恒星形成云内的圆盘上测量颗粒的生长和沉降，这是行星形成的前两步。除了研究“完整”的圆盘，PI还将瞄准正在清理其圆盘间隙的物体，这种现象最有可能是由于新形成的行星造成的。探索这些问题的主要工具将是最先进的D'Alessio磁盘模型，PI将在本建议的研究中推进到下一个复杂水平。通过将中红外斯皮策和远红外赫歇尔数据的光谱能量分布与毫米和红外干涉仪获得的空间亮度分布相结合，PI将提供一个关于圆盘中尘埃生长、沉淀和清除数量的自一致分析，这也将为詹姆斯韦伯太空望远镜（JWST）未来的圆盘研究提供指导。在整个项目中获得的系统的、半经验的证据将为尘埃演化和行星形成的理论建模提供必要的见解和约束，使我们更接近于了解我们太阳系的起源。埃斯帕拉特大学还将与哈佛大学科学导师计划一起制定正式的导师培训计划，并将为少数族裔学生建立一个类似的大学科学导师计划。通过这两个项目，PI将培训自愿担任年轻女性和少数民族研究生和本科生导师的研究生。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Dr. Catherine Espaillat is awarded an NSF Astronomy and Astrophysics Postdoctoral Fellowship to carry out a program of research and education at the Harvard-Smithsonian Center for Astrophysics. Dr. Espaillat will quantify dust evolution in protoplanetary disks around low-mass pre-main sequence stars, the precursors of our own Sun. To this end the PI will measure grain growth and settling, the first two steps towards planet formation, in disks located within the star-forming clouds of Taurus, Chamaeleon, and Ophiuchus. In addition to studying "full" disks the PI will also target objects which are in the process of clearing gaps in their disks, a phenomena which is most likely due to newly formed planets. The main tool in exploring these issues will be the state-of-the-art D'Alessio disk model, which the PI will advance to the next level of sophistication in this proposed study. By combining spectral energy distributions that employ mid-infrared Spitzer and far-infrared Herschel data with spatial brightness distributions obtained with interferometers in the millimeter and infrared, the PI will provide a self-consistent analysis of the amount of dust growth, settling, and clearing in disks, which will also serve as a guide for future disk studies with the James Webb Space Telescope (JWST). The systematic, semi-empirical evidence obtained throughout this project will provide needed insight and constraints to aid in theoretical modeling of dust evolution and planet formation, bringing us a few steps closer to understanding the origin of our own solar system.Dr. Espaillat will also develop a formal mentor-training program with the Harvard College Science Mentors Program and will establish a similar university mentoring program for minority students in science. Through these two programs the PI will train graduate students who have volunteered to serve as mentors to younger women and minority graduate and undergraduate students.