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arXiv · astro-ph/9912162

Young stellar kinematic groups and their relation with young open clusters, star forming regions and the Gould Belt

Abstract

Stellar kinematic groups (SKG) are kinematically coherent groups of stars that share a common origin. We have compiled (Montes et al. 1999; 2000) a sample of late-type stars of previously established members and possible new candidates to different young SKG (Local Association (20 - 150 Myr), Ursa Mayor group (300 Myr), Hyades supercluster (600 Myr), IC 2391 supercluster (35 Myr) and Castor Moving Group (200 Myr)). In order to better understand the origin of these young SKG, and to be able to identify late-type stars members of the classical and the recently identified SKG, we also need to study the kinematic properties of nearby young open clusters and star forming regions. With this aim we have taken the most recent data available in the literature (including astrometric data from Hipparcos Catalogue) of the nearby young open clusters, OB associations, T associations, and other associations of young stars as TW Hya. We use these data to calculate their Galactic space motions (U, V, W) and space coordinates (X, Y, Z) and study their possible association with the different SKG as well as with the young flattened and inclined Galactic structure known as the Gould Belt.

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D. Montes. 1999-12-08. Young stellar kinematic groups and their relation with young open clusters, star forming regions and the Gould Belt. https://arxiv.org/abs/astro-ph/9912162

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