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arXiv · 1712.10143

A new compact young moving group around V1062 Sco

Siegfried Röser·Elena Schilbach·Bertrand Goldman·Thomas Henning·Attila Moor·Aliz Derekas
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Abstract

Aims. We are searching for new open clusters or moving groups in the Solar neighbourhood. Methods. We used the Gaia-TGAS catalogue, cut it into narrow proper motion and parallax slices and searched for significant spatial over-densities of stars in each slice. We then examined stars forming over-densities in optical and near-infrared colour-magnitude diagrams to determine if they are compatible with isochrones of a cluster. Results. We detected a hitherto unknown moving group or cluster in the Upper Centaurus Lupus (UCL) section of the Sco-Cen OB-association at a distance of 175 pc from the Sun. It is a group of 63 co-moving stars with ages of less than 10 to about 25 Myr. For the brightest stars, which are present in the Gaia-TGAS catalogue the mean difference between kinematic and trigonometric distance moduli is about 0:01 mag with a standard deviation of 0.11 mag. Fainter cluster candidates are found in the HSOY catalog, where no trigonometric parallaxes are available. For a subset of our candidate stars, we obtained radial velocity measurements at the MPG/ESO 2.2-metre telescope in La Silla. Altogether we found twelve members with confirmed radial velocities and parallaxes, 31 with parallaxes or radial velocities, and 20 candidates from the convergent point method. The isochrone masses of our 63 members range from 2.6 M_Sun to 0.7 M_Sun.

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Siegfried Röser, Elena Schilbach, Bertrand Goldman, Thomas Henning, Attila Moor, Aliz Derekas. 2017-12-29. A new compact young moving group around V1062 Sco. https://doi.org/10.1051/0004-6361%2F201732213

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