Asteroseismic Signatures of Small Convective Cores

Abstract

We present an analytical study of the effect of small convective cores on the oscillations of solar-like pulsators. Based on an asymptotic analysis of the wave equation near the center of the star, we derive an expression for the perturbations to the frequencies of radial modes generated by a convective core and discuss how these perturbations depend on the properties of the core. Moreover, we propose a diagnostic tool to isolate the predicted signature of the core, constructed from a particular combination of the oscillation frequencies, and we validate this tool with simulated data. We also show that the proposed tool can be applied to the pulsation data soon expected from satellite missions such as CoRoT and Kepler to constrain the amplitude of the discontinuity in the sound speed at the edge of the convective core, the ratio between the sound speed and the radius at this same location, and the stellar age.

10 pages including 5 figures, ApJ accepted

References in corpus (8)

• An asteroseismic signature of helium ionization
• Most Detects G- and P-Modes in the B Supergiant HD 163899 (B2Ib/II)
• Discovery of the new slowly pulsating B star HD 163830 (B5II/III) from MOST spacebased photometry
• Asteroseismic Diagnostics of Stellar Convective Cores
• Discovery of hybrid $\gamma$ Dor and $\delta$ Sct pulsations in BD+18 4914 through MOST spacebased photometry
• 12 Bootis: a test bed for extra-mixing processes in stars
• Asteroseismology with the WIRE satellite. I. Combining Ground- and Space-based Photometry of the Delta Scuti Star Epsilon Cephei
• MOST Photometry of the roAp Star HD 134214

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