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arXiv · 0804.1276

Radial Velocity Variable sdO/Bs from SPY - Preliminary Orbits of Three New Short Period Binaries

S. Geier·U. Heber·R. Napiwotzki
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Abstract

We present new results from follow-up time-resolved spectroscopy of radial velocity variable hot subdwarfs from the SPY project. Medium resolution spectra were taken at the ESO NTT. Preliminary orbital solutions are presented for three single-lined sdO/B binaries. The orbital periods of all binaries are short and the companions are most likely white dwarfs or late main-sequence stars. Follow-up time-resolved spectroscopy is necessary to measure the orbital parameters with higher accuracy. Light curves should be taken in order to search for reflection effects and or eclipses.

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S. Geier, U. Heber, R. Napiwotzki. 2008-04-08. Radial Velocity Variable sdO/Bs from SPY - Preliminary Orbits of Three New Short Period Binaries. https://arxiv.org/abs/0804.1276

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