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arXiv · 1110.1375

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 (\Delta \nu), the small frequency separation between modes of l=0 and l=2 (\delta \nu_02), and the dimensionless offset (\epsilon). These measurements allow us to construct asteroseismic diagrams, namely the so-called C-D diagram of \delta \nu_02 versus \Delta \nu, and the recently re-introduced {\epsilon} 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 {\epsilon} and T_eff that allows for the unambiguous determination of radial order and should help resolve the problem of mode identification in F stars.

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Timothy R. White, Timothy R. Bedding, Dennis Stello, Thierry Appourchaux, Jérôme Ballot, Othman Benomar, Alfio Bonanno, Anne-Marie Broomhall, Tiago L. Campante, William J. Chaplin, Jørgen Christensen-Dalsgaard, Enrico Corsaro, Gülnur Doğan, Yvonne P. Elsworth, Stephen T. Fletcher, Rafael A. García, Patrick Gaulme, Rasmus Handberg, Saskia Hekker, Daniel Huber, Christoffer Karoff, Hans Kjeldsen, Savita Mathur, Benoit Mosser, Mario J. P. F. G. Monteiro, Clara Régulo, David Salabert, Victor Silva Aguirre, Michael J. Thompson, Graham Verner, Robert L. Morris, Dwight T. Sanderfer, Shawn E. Seader. 2011-10-06. Asteroseismic diagrams from a survey of solar-like oscillations with Kepler. https://doi.org/10.1088/2041-8205/742/1/l3

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