The Radius-Luminosity Relation from Near-Infrared Interferometry: New M Dwarf Sizes from the CHARA Array

摘要

We present interferometric size measurements of M dwarfs obtained with the Center for High Angular Resolution Astronomy (CHARA) Array on Mount Wilson. Observations were made in the near infrared K'-band,which yielded angular diameters less than one milliarcsecond and linear radii ranging from R/R_(⊙)=0.25 to 0.7. By combining our data with nearinfrared photometry and parallaxes, we have produced an observer's radiusluminosity relationship for "single" (not in eclipsing binary systems) main sequence stars smaller than our Sun. As with low-mass stars in eclipsing binary systems, we also find that many stars are 10-15% larger than predicted. We find that a dependency on metallicity may play a larger role than previously thought such that stars become significantly larger with increasing metallicity.