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arXiv · 1309.1172

A Gyrochronology and Microvariability Survey of the Milky Way's Older Stars Using Kepler's Two-Wheels Program

Saurav Dhital·Terry D. Oswalt·Philip S. Muirhead·Kolby L. Weisenburger·Sydney A. Barnes·Kenneth A. Janes·Andrew A. West·Kevin R. Covey·Soren Meibom·Trisha F. Mizusawa
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Abstract

Even with the diminished precision possible with only two reaction wheels, the Kepler spacecraft can obtain mmag level, time-resolved photometry of tens of thousands of sources. The presence of such a rich, large data set could be transformative for stellar astronomy. In this white paper, we discuss how rotation periods for a large ensemble of single and binary main- sequence dwarfs can yield a quantitative understanding of the evolution of stellar spin-down over time. This will allow us to calibrate rotation-based ages beyond ~1 Gyr, which is the oldest benchmark that exists today apart from the Sun. Measurement of rotation periods of M dwarfs past the fully-convective boundary will enable extension of gyrochronology to the end of the stellar main-sequence, yielding precise ages (σ ~10%) for the vast majority of nearby stars. It will also help set constraints on the angular momentum evolution and magnetic field generation in these stars. Our Kepler-based study would be supported by a suite of ongoing and future ground-based observations. Finally, we briefly discuss two ancillary science cases, detection of long-period low-mass eclipsing binaries and microvariability in white dwarfs and hot subdwarf B stars that the Kepler Two-Wheels Program would facilitate.

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Saurav Dhital, Terry D. Oswalt, Philip S. Muirhead, Kolby L. Weisenburger, Sydney A. Barnes, Kenneth A. Janes, Andrew A. West, Kevin R. Covey, Soren Meibom, Trisha F. Mizusawa. 2013-09-10. A Gyrochronology and Microvariability Survey of the Milky Way's Older Stars Using Kepler's Two-Wheels Program. https://arxiv.org/abs/1309.1172

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