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arXiv · 1909.04612

Gaia 8: Discovery of a star cluster containing beta Lyrae -- and of a larger old (extinct) star formation complex surrounding it

U. Bastian
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Abstract

Aims: To try and clarify whether there are stars in the neighbourhood of $\beta$ Lyrae which are physically connected to the famous prototype eclipsing binary. Methods: Scrutinize the astrometric and photometric data (from Hipparcos and Gaia DR2) of stars in a limited sky field around $\beta$~Lyrae. Results: A star cluster of about 100 members is discovered, nicely centered on $\beta$~Lyrae in 5 dimensions. There are clear indications that the newly discovered cluster belongs to a larger old (extinct) star formation complex, including two already known star clusters and an extended strewn field of stars at practically the same distance and space velocity.} Conclusions: This discovery opens up the possibility of determining a precise distance and a precise age for $\beta$ Lyrae, using the combined properties of the cluster members. This in turn may provide an important asset for an improved astrophysical interpretation of the model binary $\beta$ Lyrae and its kin. --- The larger old star formation complex is of scientific interest in its own right.

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U. Bastian. 2019-09-10. Gaia 8: Discovery of a star cluster containing beta Lyrae -- and of a larger old (extinct) star formation complex surrounding it. https://doi.org/10.1051/0004-6361%2F201936595

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