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Asteroseismology of sdB stars with FUSE

Kuassivi·A. Bonanno·R. Ferlet·B. Roberts·J. Caplinger
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Abstract

The hot subdwarf B (sdB) stars form an homogeneous group populating an extension of the horizontal branch (HB) in the ($T_{\rm eff}$--$\log g$) diagram towards temperatures up to 40,000 K. The recent discovery that many of them are multimode pulsators has triggered a large observational and theoretical effort. We discuss the possibility of performing space-based asteroseismology with {\em FUSE}, and we demonstrate that periodic luminosity variations are already detectable in archival TTAG data of sdB stars. In particular, we report on the {\em FUSE} observation of the pulsator PF 1219+534, which shows the presence of periodic variations at 6.9 mHz and 7.8 mHz, consistent with those reported from ground--based observations.

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Kuassivi, A. Bonanno, R. Ferlet, B. Roberts, J. Caplinger. 2004-11-13. Asteroseismology of sdB stars with FUSE. https://arxiv.org/abs/astro-ph/0411371

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