Cool Stars 14 - Submitted Abstract # 225
This version created on 05 October 2006

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


David H. Berger, University of Michigan
Theo A. ten Brummelaar, Georgia State University/CHARA
Douglas R. Gies, Georgia State University/CHARA
Todd J. Henry, Georgia State University/CHARA
Harold A. McAlister, Georgia State University/CHARA
Antoine Merand, Georgia State University/CHARA
Judit Sturmann, Georgia State University/CHARA
Laszlo Sturmann, Georgia State University/CHARA
Jason P. Aufdenberg, Embry-Riddle Aeronautical University
Stephen T. Ridgway, National Optical Astronomy Observatory

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_Sun=0.25 to 0.7.  By combining our data
with near-IR photometry and parallaxes, we have produced an observer's
radius-luminosity 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.

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