SCYON Abstract

Received on June 29 2001

Late-type stars members of young stellar kinematic groups. I. Single stars

Authors	Montes D., Lopéz-Santiago J., Gálvez M.C., Fernández-Figueroa M.J., De Castro E., Cornide M.
Affiliation	Departamento de Astrofísica, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
Accepted by	Monthly Notices of the Royal Astronomical Society
Contact	dmg@astrax.fis.ucm.es
URL	http://www.ucm.es/info/Astrof/skg/skg_catalogue.html
Links	Pleiades / IC 2391 / Ursa Major / Hyades

Abstract

This is the first paper of a series aimed at studying the properties of late-type stars members of young stellar kinematic groups. We center our study in classical young moving groups as: Local Association (Pleiades moving group, 20 - 150 Myr), IC 2391 supercluster (35 Myr), Ursa Major group (Sirius supercluster, 300 Myr), and Hyades supercluster (600 Myr); as well as in recently identified groups as: Castor moving group (200 Myr).

In this paper we have compiled a preliminary list of single late-type stars possible members of some of these young stellar kinematic groups. Stars have been selected from previously established members of stellar kinematic groups based in photometric and kinematic properties as well as from candidates based in other criteria as their level of chromospheric activity, rotation rate, lithium abundance. Precise measurements of proper motions and parallaxes taken from Hipparcos Catalogue, as well as from Tycho-2 Catalogue, and published radial velocity measurements are used to calculate Galactic space motions (U, V, W) and apply the Eggen's kinematic criteria in order to determine the membership of the selected stars to the different groups. Additional criteria using age-dating methods for late-type stars will be applied in forthcoming papers of this series.

A further study of the list of stars compiled here could lead to a better understanding of the chromospheric activity and their age evolution as well as of the star formation history in the solar neighbourhood. In addition, these stars are also potential search targets for direct imaging detection of sub-stellar companions.