Non-radial modes in cool stars

D. Stello

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arXiv · 1107.1311

Non-radial modes in cool stars

D. Stello

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Abstract

In cool stars that oscillate like the Sun, non-radial modes become mixed as the stars evolve. The mixing is caused by the coupling between g-modes in the stellar core and p-modes in the envelope, which results in distinctly different and more complex frequency spectra for subgiants and red giants than seen in main sequence stars. Using a new version of the `scaled' échelle diagram, I illustrate how the frequencies of non-radial modes evolve during the evolution from the main sequence to the red giant branch, and I show how they depend on stellar mass and metallicity. Then, with focus on the dipole (l = 1) modes, which show the strongest effects from mixing, I present a toy model to fit, and hence identify, those modes in a large series red giant models.

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D. Stello. 2011-07-18. Non-radial modes in cool stars. https://arxiv.org/abs/1107.1311

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