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arXiv · 1204.0928

Binary properties of subdwarfs selected in the GALEX survey

Adela Kawka·Andrzej Pigulski·Simon O'Toole·Stephane Vennes·Peter Nemeth·Andrew Williams·Lubomir Iliev·Zbyszek Kolaczkowski·Marek Steslicki
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Abstract

We describe our programme to identify and analyse binary stars among the bright subdwarfs selected in the Galaxy Evolution Explorer (GALEX) survey. Radial velocity time-series helped us identify subdwarfs with low-mass or compact stellar companions: We describe work conducted on the bright binaries GALEX J0321+4727 and GALEX J2349+3844, and we present a radial velocity study of several objects that include three new likely binaries. We also carried out photometric observations that allowed us to detect long period pulsations in the subdwarf components in two of the close binaries.

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Adela Kawka, Andrzej Pigulski, Simon O'Toole, Stephane Vennes, Peter Nemeth, Andrew Williams, Lubomir Iliev, Zbyszek Kolaczkowski, Marek Steslicki. 2012-04-04. Binary properties of subdwarfs selected in the GALEX survey. https://arxiv.org/abs/1204.0928

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