Montes, David

Contact Email: dmg@astrax.fis.ucm.es
Institute: Departamento de Astrofísica, Facultad de
Físicas, Universidad Complutense de Madrid, UCM
E-28040 Madrid, Spain.
First Coauthor: J. López-Santiago
Institute: Departamento de Astrofísica, UCM
Second Coauthor: M.C. Gálvez
Institute: Departamento de Astrofísica, UCM
Research URL:http://www.ucm.es/info/Astrof/actividad.html
Subject Area: Star Clusters, Associations
Waveband: Optical
Technique: Spectroscopy
Presentation: Poster Display
Title: Spectroscopic survey of late-type stars possible members of young moving groups
Abstract: We summarize here our ongoing high resolution echelle spectroscopic survey of late-type stars, identified in our previous studies as possible members of young moving groups: (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)). The spectroscopic observations were taken during five observing runs: July 1999 using the FOCES echelle spectrograph at the 2.2m telescope (CAHA, Almería), November 1999 and 2000 using the SOFIN echelle spectrograph at the Nordic Optical Telescope (NOT) (La Palma) and January 2000 and August 2000 using the MUSICOS echelle spectrograph at the Isaac Newton Telescope (INT) (La Palma). Our main goal is to analyse in more detail the membership of these stars to the different young stellar kinematic groups. On one hand we have tested its kinematic membership by calculating the Galactic space motion (U, V, W) using radial velocities determined in our spectra by cross correlation with radial velocity standard stars. On the other hand we have used age-dating methods for late-type stars such as the chromospheric activity level and the lithium absorption line. The chromospheric activity level of these stars has been analysed using the information provided for several optical spectroscopic features (from the Ca  II H & K to Ca  II IRT lines). The Li  I $\lambda$6707.8 Å$\$ line equivalent width (EW) has been determined and compared with lithium EW of stars of different well known young open clusters.