CAREER: Fixing Stellar Chronometers With Open Clusters

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A star's age is one of its most fundamental parameters. It is also, for isolated 'field' stars, notoriously difficult to measure accurately. Two standard stellar chronometers - the age-rotation and age-activity relations - generally struggle to produce age estimates with uncertainties better than 50%. The PI will tackle this problem by combining a wealth of new observations from the Palomar Transient Factory Open Cluster Survey with follow-up spectroscopy and X-ray observations. He will assemble a complete, uniform sample of rotation periods and activity measurements for low-mass stars in six open clusters ranging in age from 35 Myr to 2.5 Gyr. By examining the relationships between stellar age, rotation, and activity, he will address three basic questions: (1) the rotational period distribution of low mass zero-age main sequence stars, (2) the evolution of rotational periods of low mass stars with ages 500 My, and (3) the possible divergence of age-activity and age-rotation relations at ages 500 My. The work will provide a significant leap in our understanding of stellar ages. In turn, this will inform us about the composition and internal structure of stars, and it will allow us to better understand stellar magnetic fields. The PI will also perform a wide-ranging set of synergistic education and outreach activities centered on ensuring that students from underrepresented minorities have successful transitions into graduate school. As the Director of Columbia University's Bridge to the Ph.D. in the Natural Sciences scheme, he will play a leading role in recruiting, mentoring, and educating post-baccalaureate minority students in a structured program designed to ensure their continued success in Ph.D. programs.