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arXiv · 0803.2255

Might Carbon-Atmosphere White Dwarfs Harbour a New Type of Pulsating Star?

G. Fontaine·P. Brassard·P. Dufour
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Abstract

In the light of the recent and unexpected discovery of a brand new type of white dwarfs, those with carbon-dominated atmospheres, we examine the asteroseismological potential of such stars. The motivation behind this is based on the observation that past models of carbon-atmosphere white dwarfs have partially ionized outer layers that bear strong resemblance with those responsible for mode excitation in models of pulsating DB (helium-atmosphere) and pulsating DA (hydrogen-atmosphere) white dwarfs. Our exciting main result is that, given the right location in parameter space, some carbon-atmosphere white dwarfs are predicted to show pulsational instability against gravity modes. We are eagerly waiting the results of observational searches for luminosity variations in these stars.

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G. Fontaine, P. Brassard, P. Dufour. 2008-03-14. Might Carbon-Atmosphere White Dwarfs Harbour a New Type of Pulsating Star?. https://doi.org/10.1051/0004-6361:200809651

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