Precision Masses of the Low-Mass Binary System GJ 623
Ireland, Michael J.; Martinache, Frantz; Lloyd, James P.; Tuthill, Peter G.; Yamada, Ryan S.
United States, Australia
Abstract
We have used aperture masking interferometry and adaptive optics (AO) at the Palomar 200 inch telescope to obtain precise mass measurements of the binary M dwarf GJ 623. AO observations spread over 3 yr combined with a decade of radial velocity measurements constrain all orbital parameters of the GJ 623 binary system accurately enough to critically challenge the models. The dynamical masses measured are m1=0.371+/-0.015 Msolar (4%) and m2=0.115+/-0.0023 Msolar (2%) for the primary and the secondary, respectively. Models are not consistent with color and mass, requiring very low metallicities.