Stars with partially convective atmospheres (0.3 < M < 0.8 M_solar) are observed to have radii 10-20% larger than models predict when members of biinary systems. One leading theory is that tidal rotational synchronization generates larger magnetic fields in these stars than they would have otherwise. This leads to a decrease in effective temperature, and the radius expands to compensate. I am currently studying EB's with at least one component in the mass range above, and with orbital periods P > 5 days, to better understand how this effect scales with rotation rates and therefore magnetic field strengths. I also want to study how this scales with stellar mass (convection zone depth). To obtain a large sample, I am using data from extrasolar planet surveys (Doppler and transit), since these surveys discovery large amounts of binary systems as part of their quest for planets, yet often do not have the resources to conduct the binary science that is available with the data.
Spectroscopic followup of eclipsing binaries in the context of the mass-radius relationship.