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arXiv · astro-ph/0401201

Close binary EHB stars from SPY

R. Napiwotzki·C. A. Karl·T. Lisker·U. Heber·N. Christlieb·D. Reimers·G. Nelemans·D. Homeier
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Abstract

We present the results of a radial velocity (RV) survey of 46 subdwarf B (sdB) and 23 helium-rich subdwarf O (He-sdO) stars. We detected 18 (39%) new sdB binary systems, but only one (4%) He-sdO binary. Orbital parameters of nine sdB and sdO binaries, derived from follow-up spectroscopy, are presented. Our results are compared with evolutionary scenarios and previous observational investigations.

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R. Napiwotzki, C. A. Karl, T. Lisker, U. Heber, N. Christlieb, D. Reimers, G. Nelemans, D. Homeier. 2004-01-12. Close binary EHB stars from SPY. https://doi.org/10.1023/b%3Aastr.0000044362.07416.6c

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