Wide Low-Mass Binaries: Coeval Laboratories for Testing the Formation and Evolution of Stars, and the Structure and Evolution of the Milky Way

点击翻译按钮获取中文摘要

AST-0909463StassunThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).M-dwarfs (dMs) make up about seventy percent of the stars in our Galaxy and have main sequence lifetimes longer than the age of the Galaxy. They are therefore useful probes of the structure and evolution of the Milky Way. Low-mass binaries are important coeval laboratories for testing empirical relations, as the two stars likely formed from the same material at the same time. This project will construct the largest sample of wide low-mass binaries ever assembled, and then use this sample to: (a) study the role of multiplicity in the formation of low-mass stars; (b) test and calibrate the mass-age-activity-rotation relationships that are central to stellar age determinations and that are used to determine the basic properties of exoplanet host stars; and (c) trace the history of dynamical interactions in the Milky Way. Building on the identification of all wide low-mass binaries in the Sloan Digital Sky Survey, spectroscopic observations, time-series photometry, and adaptive optics imaging of these binaries will address the following questions. 1) What is the intrinsic scatter of activity in low-mass dwarfs? 2) What is the activity of low-mass stars as a function of mass and time? 3) What is the absolute age-activity relationship in dMs? 4) What is the survival rate of wide binaries over time? 5) Do the components of wide binaries have the same close multiplicity statistics as low-mass stars not in wide systems?The project team has a joint program between Vanderbilt and Fisk Universities of education and research mentoring at the undergraduate, graduate, and postdoctoral levels, which significantly enhances and broadens the participation of underrepresented minorities in astronomy. The present research includes a plan to continue and expand upon the undergraduate and graduate programs. It also includes an excellent professional development opportunity for a postdoctoral researcher seeking experience integrating research and student mentoring.