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Centro de Astrofísica da Universidade do Porto

Oscillations in g-mode period spacings in red giants as a way to determine their state of evolution

M. S. Cunha, D. Stello, P. P. Avelino, J. Christensen-Dalsgaard

Abstract
In this work we consider the sensitivity of gravity-mode period spacings to sharp changes in the inner structure of red giant stars, more specifically in the buoyancy frequency inside the g-mode propagation cavity. Based on a comparison between the solutions to the linear pulsation equations in the Cowling approximation for pure g-modes with results obtained with a full oscillation code we identify and correctly interpret the signature of the above-mentioned sharp variations in the period spacings. Two examples, of red giant models in different evolutionary phases, are discussed. Detection of these signatures in CoRoT, Kepler or future PLATO red-giant stars would pin down their evolutionary state in an unprecedented way.

The Space Photometry Revolution
(Eds.) R.A. García, J. Ballot

EPJ Web of Conferences
Vol. 101, Page 01014
2015

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