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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 period distribution of unevolved close binary systems
Period distributions have been examined for various spectral types ofabout 600 (eclipsing and spectroscopic) close binaries, which are likelyto be substantially unevolved. The comparison with the previouscorresponding analyses of extensive (but heterogeneous) binary samplesallows a clarification of the extent of the evolutionary andobservational selection effects. Remarkably, this analysis reveals agreat deficiency of short period binaries (with periods corresponding tocase A mass transfer) in the whole spectral range. For the late spectraltypes, this result may be connected with postformation angular momentumloss caused by stellar wind magnetic braking; at least for the late Band A spectral range, a ready interpretation of this finding is thatclose binaries of corresponding periods and spectral types are rarelyformed.
| NGC 4650A - The rotation of the diffuse stellar component
NGC 4650A consists of two components, a diffuse central component (whichlooks much like an S0 galaxy), and a warped outer ring of H II regions.The projections of these two components onto the sky lie nearlyperpendicular to each other. Measurements have been conducted of therotation of the diffuse central component, and it is found that theratio of rotation velocity at the last measured point to the centralvelocity dispersion, is greater than unity. This is consistent with awide range of models, spanning a continuum with rapidly tumbling prolatesystems at one extreme and nontumbling oblate ones at the other. For thenearly prolate configurations and for the oblate ones the ring of H IIregions is unstable of differential precession and will settle to aposition angle closer to the projected major axis of the centralcomponent. However, there may be a relatively oblate (but stilltriaxial) configuration for which the ring lies in a stable closedorbit.
| Photoelectric photometry of selected AG stars in the 25D to 30D zone.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1968AJ.....73..187B&db_key=AST
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