Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521
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Absolute proper motions of open clusters. I. Observational data
Mean proper motions and parallaxes of 205 open clusters were determinedfrom their member stars found in the Hipparcos Catalogue. 360 clusterswere searched for possible members, excluding nearby clusters withdistances D < 200 pc. Members were selected using ground basedinformation (photometry, radial velocity, proper motion, distance fromthe cluster centre) and information provided by Hipparcos (propermotion, parallax). Altogether 630 certain and 100 possible members werefound. A comparison of the Hipparcos parallaxes with photometricdistances of open clusters shows good agreement. The Hipparcos dataconfirm or reject the membership of several Cepheids in the studiedclusters. Tables 1 and 2 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Open clusters with Hipparcos. I. Mean astrometric parameters
New memberships, mean parallaxes and proper motions of all 9 openclusters closer than 300 pc (except the Hyades) and 9rich clusters between 300 and 500 pc have been computed using Hipparcosdata. Precisions, ranging from 0.2 to 0.5 mas for parallaxes and 0.1 to0.5 mas/yr for proper motions, are of great interest for calibratingphotometric parallaxes as well as for kinematical studies. Carefulinvestigations of possible biases have been performed and no evidence ofsignificant systematic errors on the mean cluster parallaxes has beenfound. The distances and proper motions of 32 more distant clusters,which may be used statistically, are also indicated. Based onobservations made with the ESA Hipparcos astrometry satellite
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Spectroscopy of the open cluster Blanco 1 II. H alpha emission as an indicator of relative age
We present the results of H alpha (6562\AA) and Li i (6708\AA)observations of 114 low-mass stars of the young open cluster Blanco 1.We also present observations of 30 stars in Ca ii(K). This work extendsthe first Blanco 1 spectroscopic study of Panagi et al. (1994). From asample of four well-studied clusters, including Blanco 1, we find thatthe fraction of H alpha emission-line stars amongst K dwarfs is a goodindicator of relative age, with a smaller fraction indicative of olderage. Blanco 1 shows a relatively small fraction of emitters,inconsistent with previous age estimates for the cluster. We estimatethe cluster age to to be 90 +/- 25 Myr, slightly older than thePleiades. The method is shown to be more sensitive to age than lithiumand a useful alternative to other age measurement techniques. Thevariation of H alpha with (B-V) is similar to that observed in the oldersolar neighbourhood dwarfs, suggesting that, at least for theabsorption-line stars, the contribution of stellar rotation to theequivalent width is unclear. We combine both spectroscopy and photometryto revise cluster membership and give accurate positions for all thesestars. Tables A1 and A2 are available at the CDS via anonymous ftp130.79.128.5 or http://cdsweb.u-strabg.fr./Abstract.html
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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.
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UBV and uvby-beta photometry of stars in the region of the Zeta SCULPTORIS cluster
Photoelectric observations of 130 stars in the region of Zeta Sculptorishave been obtained in UBV and uvby-beta. A total of 32 stars areidentified as cluster members, and several other F and G type stars areidentified as probable members. Results indicate an interstellarreddening of E(B-V) = 0.02 mag and that the cluster is slightly metaldeficient.
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The early A type stars - Refined MK classification, confrontation with Stroemgren photometry, and the effects of rotation
The MK classification system for the early A-type stars is refined, anda parallel system of standards for the broad-lined stars is introduced.With this improved system, stars may be classified with significantlygreater precision than before. It is shown that spectral types in thissystem are not systematically affected by rotational line broadening. Atotal of 372 early A-type stars are classified, and a confrontation ofthese spectral types with Stroemgren photometry reveals a number ofsystematic photometric effects of rotation. In particular, high v sin istars are systematically redder than low v sin i stars of the samespectral type, and the beta index is weakened by rotation. It isconcluded that precise spectral classification in conjunction withStroemgren and H-beta photometry can potentially provide a valuablecheck and input to the theory of the atmospheres of rotating stars.
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Photometric study of Zeta SCULPTORIS cluster
Photographic photometry of about 1500 stars in the region of the ZetaSculptoris cluster has been accomplished, and relations between thisphotometry and broad- and intermediate-band photoelectric photometryestablished. From observation of the H-R diagrams, it is concluded thatabout 150 stars belong to the unevolved main sequence of the cluster. Asmall reddening of E(B - V) = 0.013 m similar to values given by otherauthors, and a mean modulus of about 6.9 mag, have been determined. Twogaps exist in the main sequence, one between (B - V) about 0.06 m andabout 0.30 m and the other around (B - V) about 1.00.
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The common origin of some open clusters
Eight open clusters have been observed with uvby-beta photometry and forseven of them the metal abundances have been determined. Six of thesehave similar metallicities. They are close in space and are also knownto have similar ages and radial velocities. These clusters are suspectedof having a common origin. Some studies are made of the reliability ofthe photometric system. A large gain in limiting magnitude can beachieved against an unimportant loss of accuracy if interference filtersare removed.
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Interstellar reddening towards the south galactic pole
B, A and F type stars are observed in an area of about 400 squaredegrees around the galactic south pole (SGP) using theStroemgren-Crawford uvby-beta system at the 60 cm telescope of theBochum station on La Silla, Chile. With calibrations for B and F typestars and the provisional calibration for the stars of Stroemgren's LateGroup-A-stars, intrinsic (b-y)0 colors are derived and then used todescribe the interstellar absorption structure of the SGP. To determinethe galactic extinction perpendicular to the galactic plane, thereddening values of distant stars are averaged in order to include boththe reddened and unreddened areas at the SGP. A mean value E(b-y)SGPequals 0.019 m is derived and is found to agree well with earliervalues, except with that of Knude (1977). Explanations for the deviationare considered, implying that Knude's value is systematically too high.
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Spectral types in the Zeta SCULPTORIS open cluster
The spectral types of 20 stars in the Blanco 1 open cluster (ZetaSculptoris) are reported. Spectral classification in the MK system wasperformed on the basis of 125-A/mm dispersion spectra obtained with a0.9-m telescope and a Cassegrain spectrograph. Of the stars classified,one classical Am star, one peculiar star with a weak K-line and one Apstar with marginal Si II lines enhancement were found, while the starZeta Scl itself is observed to be a main sequence object and thusprobably a foreground star. An H-R diagram of the cluster is alsopresented, and other probable members and nonmembers are indicated.
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Multicolor photometry of the ZET Scl open cluster.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978PASP...90...81P&db_key=AST
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NGC 2516 and the Pleiades Group
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972ApJ...173...63E&db_key=AST
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Radial Velocities and Spectral Classification of A-Type Stars Near the South Galactic Pole
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971PASP...83..643B&db_key=AST
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A finding list of early-type stars near the south galactic pole.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971AJ.....76..338S&db_key=AST
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A Very Young Cluster with a Moderate Metal Deficiency
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJ...161..159E&db_key=AST
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Four-color photoelectric photometry of two high-latitude clusters.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1968AJ.....73..556E&db_key=AST
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Three-colour photometry of early-type stars near the galactic poles
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963MNRAS.127...83W&db_key=AST
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INHABITED SKY
