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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
| DDO Metal Abundances of High-Luminosity Late-Type Stars in Galactic Open Clusters Results from UBV and DDO photometry are presented for 54 high-luminositylate-type stars in the fields of 23 open clusters. The probability ofcluster membership for each observed star is evaluated using twoindependent photometric criteria. It is found that 32 stars are verylikely cluster members, the remaining ones being almost certainly fieldobjects. The recently improved calibrations of the DDO system have beenused to derive MK spectral types, effective temperatures, andmetallicities, while E(B-V) color excesses have been determined throughknown photometric and spectroscopic procedures. The DDO metallicitiesrange between values typical of moderately metal-poor ([Fe/H]=~ -0.3) tomoderately metal-rich ([Fe/H] =~ 0.2) clusters. The masses of thecluster giants range between 1 and 4 solar masses, with the scatterwithin a cluster being less than 1 solar mass. (SECTION: StellarClusters and Associations)
| Memberships and CM diagrams of young open clusters. I - NGC 225 Results are presented on astrometric, photometric, and spectroscopicstudies of the loose young open cluster NGC 225, conducted on the basisof observations and archived plate material. The main cluster parametersderived in this study are presented in the form of a table. Astrometricmember candidates were checked against photometric and spectroscopiccriteria, yielding an enhanced list of cluster members which is suitablefor further and more extensive investigations.
| Yellow evolved stars in open clusters This paper describes a program in which Galactic cluster post-AGBcandidates were first identified and then analyzed for clustermembership via radial velocities, monitored for possible photometricvariations, examined for evidence of mass loss, and classified ascompletely as possible in terms of their basic stellar parameters. Theintrinsically brightest supergiants are found in the youngest clusters.With increasing cluster age, the absolute luminosities attained by thesupergiants decline. It appears that the evolutionary tracks ofluminosity class II stars are more similar to those of class I than ofclass III. Only two superluminous giant star candidates are found inopen clusters.
| Photoelectric observations of classical cepheids. Not Available
| Yellow giants in young clusters. I - Photometric observations To enable a study of the properties of luminous yellow stars, a list hasbeen compiled of 84 stars which appear to be in the appropriate regionin the color-magnitude diagrams of 41 young clusters. Proper motions,radial velocities, UBV photometry, and spectral types from theliterature have been used in those cases where such data are availableto assign membership probabilities. DDO and uvby photometry have alsobeen obtained of most of the stars in the list, and these data areanalyzed to remove stars from the sample which have the wrong luminosityor the wrong color excess for cluster membership. In addition, VRIphotometry is given for many of the stars in the list. Based on thesedata, 22 of the stars (26 percent) from the original sample are likelycluster members, while 48 (57 percent) are not likely to be members. Theremainder must be studied further to determine their status, but it isprobable that some of them are also in clusters.
| Evolved stars in open clusters. Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976ApJS...30..451H&db_key=AST
| (R-I) colors of cepheids and yellow supergiants in open clusters. Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976ApJ...203..466S&db_key=AST
| Distance Moduli of Open Clusters. Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1965ApJS...12..215H&db_key=AST
| Spectral Classification in Nine Open Clusters. Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1962ApJ...136..788S&db_key=AST
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