A PRECISE ASTEROSEISMIC AGE AND RADIUS FOR THE EVOLVED SUN-LIKE STAR KIC 11026764

Abstract

The primary science goal of the Kepler Mission is to provide a census of\nexoplanets in the solar neighborhood, including the identification and\ncharacterization of habitable Earth-like planets. The asteroseismic\ncapabilities of the mission are being used to determine precise radii and ages\nfor the target stars from their solar-like oscillations. Chaplin et al. (2010)\npublished observations of three bright G-type stars, which were monitored\nduring the first 33.5 days of science operations. One of these stars, the\nsubgiant KIC 11026764, exhibits a characteristic pattern of oscillation\nfrequencies suggesting that it has evolved significantly. We have derived\nasteroseismic estimates of the properties of KIC 11026764 from Kepler\nphotometry combined with ground-based spectroscopic data. We present the\nresults of detailed modeling for this star, employing a variety of independent\ncodes and analyses that attempt to match the asteroseismic and spectroscopic\nconstraints simultaneously. We determine both the radius and the age of KIC\n11026764 with a precision near 1%, and an accuracy near 2% for the radius and\n15% for the age. Continued observations of this star promise to reveal\nadditional oscillation frequencies that will further improve the determination\nof its fundamental properties.\n