Asteroseismic diagrams from a survey of solar-like oscillations with Kepler

Abstract

Photometric observations made by the NASA Kepler Mission have led to a dramatic increase in the number of main-sequence and subgiant stars with detected solar-like oscillations. We present an ensemble asteroseismic analysis of 76 solar-type stars. Using frequencies determined from the Kepler time-series photometry, we have measured three asteroseismic parameters that characterize the oscillations: the large frequency separation (Δν), the small frequency separation between modes of l = 0 and l = 2 (δν02) , and the dimensionless offset (ε). These measurements allow us to construct asteroseismic diagrams, namely the so-called Christensen-Dalsgaard diagram of δν02 versusΔν, and the recently re-introduced ε diagram. We compare the Kepler results with previously observed solar-type stars and with theoretical models. The positions of stars in these diagrams places constraints on their masses and ages. Additionally, we confirm the observational relationship between ε and T eff that allows for the unambiguous determination of radial order and should help resolve the problem of mode identification in F stars. © 2011. The American Astronomical Society. All rights reserved.