Seismic signatures of stellar cores of solar-like pulsators: Dependence on mass and age

Brandão, I. M.; Cunha, M. S.; Creevey, O. L.; Christensen-Dalsgaard, J.
Bibliographical reference

Astronomische Nachrichten, Vol.331, Issue 9/10, p.940

Advertised on:
12
2010
Number of authors
4
IAC number of authors
0
Citations
10
Refereed citations
10
Description
Useful information from the inner layers of stellar pulsators may be derived from the study of their oscillations. In this paper we analyse three diagnostic tools suggested in the literature built from the oscillation frequencies computed for a set of main sequence models with masses between 1.0 M&sun; and 1.6 M&sun;, to check what information they may hold about stellar cores. For the models with convective cores ({M ≥ 1.2} M&sun;) we find a relation between the frequency slopes of the diagnostic tools and the size of the jump in the sound speed at the edge of the core. We show that this relation is independent of the mass of the models. In practice, since the size of the jump in the sound speed is related to the age of the star, using these seismic tools we may, in principle, infer the star's evolutionary state. We also show that when combining two of the three diagnostic tools studied, we are able to distinguish models with convective cores from models without a convective core but with strong sound speed gradients in the inner layers
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