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Activity in Solar-Type Stars by Frank C. Fekel 16 November 2001 A brief overview will be given of research being conducted with Tennessee State University's 7 automated telescopes at Fairborn Observatory in southeastern Arizona. In particular an extensive survey to define changes in luminosity of solar-type stars will be discussed. This sample consists of 162 late-F to early-K dwarfs and subgiants. Photometric observations with a nightly precision of 0.001 mag and 0.0001 mag for yearly means have been obtained for up to a decade. These results will be combined with Mt. Wilson measurements of chromospheric emission, a proxy for magnetic activity. Complementary high-dispersion spectroscopic observations of this stellar sample have been obtained at Kitt Peak National Observatory to determine spectral types, radial velocities, and projected rotational velocities. An analysis of this data has begun and preliminary results will be discussed including short-term and long-term light variability, the magnitude of solar brightness variations relative to our sample, and the identification of stars in Maunder Minimum episodes.
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