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Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.
| The kinematics of lithium-rich, active late-type stars: evidence for a low-mass Local Association
An EUV-selected sample of late-type stars has been observed for lithiumabundances and radial velocity radiations. It is found that essentiallyall of the single stars have lithium abundances comparable to or greaterthan late-type stars in the Pleiades. These observations have confirmedthe hypothesis that a high proportion of the most coronally active,late-type stars are Li-rich, because they are young, have not yet spundown, and consequently exhibit enhanced dynamo activity. From these dataand other activity-selected samples in the literature, a Li-rich sampleof single stars has been chosen, which, by comparison with open clusterLi abundances and rotation rates, is substantially younger than 300 Myr.The kinematics of this sample has been investigated, and from the radialvelocities a one-dimensional dispersion of only 5.7 km s^-1 is found,about a centroid space motion extremely similar to that of a group ofyoung open clusters and nearby B stars, known as the Local Association.Consideration of the space motions confirms that, if this low-mass LocalAssociation can be represented by a three-dimensional velocitydispersion of about 10 km s^-1, then the majority of the Li-rich starsare members. The origin of the Local Association is still obscure, but anumber of suggestions are put forward, including ejection of stars fromnearby open clusters, the disruption of pre-existing clusters, or thedissolution of the unbound remnants from one or more star formationregions.
| Empirical temperature calibrations for early-type stars
Three temperature calibrations of suitable photometric quantities havebeen derived for O and B stars. A sample of 120 stars with reliableT(eff.) determinations has been used for establishing each calibration.The different calibrations have been critically discussed and compared.Temperature determinations for 1009 program stars have been obtainedwith an accuracy of the order of 10 percent.
| La mesure des vitesses radiales au prisme objectif - X - 4e liste de vitesses radiales déterminées au prisme objectif à vision directe
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