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

Abstract

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 $1.0{\mathrm{M}}_{\odot }$ and $1.6{\mathrm{M}}_{\odot }$, to check what information they may hold about stellar cores. For the models with convective cores ($M\ge 1.2{\mathrm{M}}_{\odot }$) 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.

References in corpus (3)

• ADIPLS -- the Aarhus adiabatic oscillation package
• ASTEC -- the Aarhus STellar Evolution Code
• Asteroseismic Signatures of Small Convective Cores

Cited by in corpus (7)

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• Near-Core Acoustic Glitches are Not Oscillatory: Consequences for Asteroseismic Probes of Convective Boundary Mixing
• Modeling of two CoRoT solar analogues constrained by seismic and spectroscopic analysis
• Estimate the radius of the convective core of main-sequence stars from observed oscillation frequencies
• On the stellar core physics of the 16 Cyg binary system: constraining the central hydrogen abundance using asteroseismology