The Interior Structure Constants as an Age Diagnostic for Low-Mass, Pre-Main Sequence Detached Eclipsing Binary Stars

Abstract

We propose a novel method for determining the ages of low-mass, pre-main sequence stellar systems using the apsidal motion of low-mass detached eclipsing binaries. The apsidal motion of a binary system with an eccentric orbit provides information regarding the interior structure constants of the individual stars. These constants are related to the normalized stellar interior density distribution and can be extracted from the predictions of stellar evolution models. We demonstrate that low-mass, pre-main sequence stars undergoing radiative core contraction display rapidly changing interior structure constants (greater than 5% per 10 Myr) that, when combined with observational determinations of the interior structure constants (with 5 -- 10% precision), allow for a robust age estimate. This age estimate, unlike those based on surface quantities, is largely insensitive to the surface layer where effects of magnetic activity are likely to be most pronounced. On the main sequence, where age sensitivity is minimal, the interior structure constants provide a valuable test of the physics used in stellar structure models of low-mass stars. There are currently no known systems where this technique is applicable. Nevertheless, the emphasis on time domain astronomy with current missions, such as Kepler, and future missions, such as LSST, has the potential to discover systems where the proposed method will be observationally feasible.

Accepted for publication in ApJ, 8 pages, 3 figures

References in corpus (25)

• The Dartmouth Stellar Evolution Database
• Accurate masses and radii of normal stars: modern results and applications
• Low Temperature Opacities
• The NextGen Model Atmosphere grid for $3000\le \Teff \le 10000\K$
• Element Diffusion in the Solar Interior
• Theory of Low-Mass Stars and Substellar Objects
• The Ages of Stars
• The NextGen Model Atmosphere grid: II. Spherically symmetric model atmospheres for giant stars with effective temperatures between 3000 and 6800~K
• Evolution of low-mass star and brown dwarf eclipsing binaries
• Metallicity and Temperature Indicators in M dwarf K band Spectra: Testing New & Updated Calibrations With Observations of 133 Solar Neighborhood M dwarfs
• Helioseismological Implications of Recent Solar Abundance Determinations
• The ACS Survey of Galactic Globular Clusters. II. Stellar Evolution Tracks, Isochrones, Luminosity Functions, and Synthetic Horizontal-Branch Models
• KOI-126: A Triply-Eclipsing Hierarchical Triple with Two Low-Mass Stars
• The effect of magnetic activity on low-mass stars in eclipsing binaries
• Masses and Radii of Low-Mass Stars: Theory versus Observations
• Misaligned spin and orbital axes cause the anomalous precession of DI Herculis
• Reevaluating the Mass-Radius Relation for Low-Mass, Main Sequence Stars
• Heavy Element Diffusion in Metal Poor Stars
• Self-Consistent Magnetic Stellar Evolution Models of the Detached, Solar-Type Eclipsing Binary EF Aquarii
• Accurate Low-Mass Stellar Models of KOI-126
• Theoretical Uncertainties in Red Giant Branch Evolution: The Red Giant Branch Bump
• The radii of M-dwarfs in the young open cluster NGC 2516
• The OPAL Equation of State and Low Metallicity Isochrones
• The Effect of Star Spots on Accurate Radius Determination of the Low Mass Double-lined Eclipsing Binary GU Boo
• The Triply Eclipsing Hierarchical Triple Star KIC002856960

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• Magnetic Inhibition of Convection and the Fundamental Properties of Low-Mass Stars. III. A Consistent 10 Myr Age for the Upper Scorpius OB Association
• The Rotation-Activity Correlations in K and M dwarfs. II. New constraints on the dynamo mechanisms in late-K and M dwarfs before and at the transition to complete convection
• Photodynamical Modeling of the Fascinating Eclipses in the Triple-Star System KOI-126
• Accretion process, magnetic fields, and apsidal motion in the pre-main sequence binary DQ Tau
• Orbital characterization of GJ1108A system, and comparison of dynamical mass with model-derived mass for resolved binaries