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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New Observations on Classical Cepheids DL Cas and FM Cas
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A catalog of rotational and radial velocities for evolved stars
Rotational and radial velocities have been measured for about 2000evolved stars of luminosity classes IV, III, II and Ib covering thespectral region F, G and K. The survey was carried out with the CORAVELspectrometer. The precision for the radial velocities is better than0.30 km s-1, whereas for the rotational velocity measurementsthe uncertainties are typically 1.0 km s-1 for subgiants andgiants and 2.0 km s-1 for class II giants and Ib supergiants.These data will add constraints to studies of the rotational behaviourof evolved stars as well as solid informations concerning the presenceof external rotational brakes, tidal interactions in evolved binarysystems and on the link between rotation, chemical abundance and stellaractivity. In this paper we present the rotational velocity v sin i andthe mean radial velocity for the stars of luminosity classes IV, III andII. Based on observations collected at the Haute--Provence Observatory,Saint--Michel, France and at the European Southern Observatory, LaSilla, Chile. Table \ref{tab5} also available in electronic form at CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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UBV beta Database for Case-Hamburg Northern and Southern Luminous Stars
A database of photoelectric UBV beta photometry for stars listed in theCase-Hamburg northern and southern Milky Way luminous stars surveys hasbeen compiled from the original research literature. Consisting of over16,000 observations of some 7300 stars from over 500 sources, thisdatabase constitutes the most complete compilation of such photometryavailable for intrinsically luminous stars around the Galactic plane.Over 5000 stars listed in the Case-Hamburg surveys still lackfundamental photometric data.
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Classification of Population II Stars in the Vilnius Photometric System. II. Results
The results of photometric classification of 848 true and suspectedPopulation II stars, some of which were found to belong to Population I,are presented. The stars were classified using a new calibrationdescribed in Paper I (Bartkevicius & Lazauskaite 1996). We combinethese results with our results from Paper I and discuss in greaterdetail the following groups of stars: UU Herculis-type stars and otherhigh-galactic-latitude supergiants, field red horizontal-branch stars,metal-deficient visual binaries, metal-deficient subgiants, stars fromthe Catalogue of Metal-deficient F--M Stars Classified Photometrically(MDPH; Bartkevicius 1993) and stars from one of the HIPPARCOS programs(Bartkevicius 1994a). It is confirmed that high galactic latitudesupergiants from the Bartaya (1979) catalog are giants or even dwarfs.Some stars, identified by Rose (1985) and Tautvaisiene (1996a) as fieldRHB stars, appear to be ordinary giants according to our classification.Some of the visual binaries studied can be considered as physical pairs.Quite a large fraction of stars from the MDPH catalog are found to havesolar metallicity. A number of new possible UU Herculis-type stars, RHBstars and metal-deficient subgiants are identified.
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Positions and Proper Motions in the Area of the Open Cluster NGC 129
Positions and magnitudes were derived for 537 stars in the area of theopen cluster NGC 129. Combining these positions with data from the threeother sources, proper motions could be derived for 86 stars.
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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)
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Colour excesses of F-G supergiants and Cepheids from Geneva photometry.
A reddening scale for F-G supergiants and Cepheids is presented.Supergiants with low reddenings or in clusters form the basis of thecalibration. In this sense, it is entirely empirical. The data have beenobtained in the Geneva photometric system. Comparisons with otherreddening scales show no disagreement. The only problem is with Fernie'sscale for Cepheids (1990), where a systematic trend exists. Its originis not clear. It is suggested to extend the number of supergiants withindependently obtained colour excesses in order to test the existence ofa possible luminosity dependence of the calibration. A period-colourrelation for Cepheids is deduced, on the basis of the present reddeningcorrections. It gives strong support for V473 Lyr being a secondovertone pulsator.
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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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Absolute Magnitudes and Colors of A-F Supergiants from Near-Infrared Features. II. The Galactic Sample
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995AJ....109.2193S&db_key=AST
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Estimating absolute magnitudes and colors of A-F supergiants from near-infrared features. I - The Northern Hemisphere
In this paper we consider the calibration of the luminosity sensitive OI 7774 A feature in the A and F supergiants. We have obtained 2-3 Aresolution CCD spectra of this feature for nine A and F supergiants innorthern Galactic clusters. The new data, additional cluster members,and improvements in the various distance estimates have substantiallyimproved the calibration. We show that the intrinsic rms dispersionabout the resulting M(V)-W(lambda) relation for A and F supergiants iscomparable to that of the Cepheid period luminosity relation in thevisual. We have also found that an index measuring the strength of theinfrared calcium triplet provides an excellent indicator of intrinsiccolor among these stars. Together, these two relations suggest that Aand F supergiants could usefully be employed as standard candles out toat least 5 Mpc.
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Galactic clusters with associated Cepheid variables. II - NGC 129 and DL Cassiopeiae
The paper presents new photoelectric UBV photometry of 27 stars andspectroscopic observations of 12 stars for NGC 129, the clustercontaining the 8.00-d Cepheid DL Cas. The photometry is used torestandardize previously published photoelectric and photographicobservations of stars in NGC 129, including transformed Stromgren systemdata. A compilation of the best available photometric data for starswith V less than 15.3 is used in conjunction with published propermotion data and spectroscopic observations of the brighter stars for adetailed cluster analysis. The newly obtained distance modulus of NGC129 is 11.11 +/-0.02 s.e., and a value of 3.20 +/-0.30 s.e. is found todescribe the dust extinction in the field. A list of 94 candidatecluster members is presented, and a cluster radial velocity of -36.0+/-1.8 km/s is derived using the supergiants and bright B stars. Themembership status of the supergiants is discussed in connection withother available information for cluster stars.
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Galactic OB associations in the northern Milky Way Galaxy. I - Longitudes 55 deg to 150 deg
The literature on all OB associations was reviewed, and their IRAS pointsource content was studied, between galactic longitude 55 and 150 deg.Only one third of the 24 associations listed by Ruprecht et al. (1981)have been the subject of individual studies designed to identify thebrightest stars. Distances to all of these were recomputed using themethod of cluster fitting of the B main sequence stars, which makes itpoossible to reexamine the absolute magnitude calibration of the Ostars, as well as for the red supergiant candidate stars. Also examinedwas the composite HR diagram for these associations. Associations withthe best defined main sequences, which also tend to contain very youngclusters, referred to here as OB clusters, have extremely few evolved Band A or red supergiants. Associations with poorly defined mainsequences and few OB clusters have many more evolved stars. They alsoshow an effect in the upper HR diagram referred to as a ledge byFitzpatrick and Garmany (1990) in similar data for the Large MagellanicCloud. It is suggested that the differences in the associations are notjust observational selection effects but represent real differences inage and formation history.
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Colour excesses and absolute magnitudes for non-Cepheid F-G supergiants from uvbybeta photometry
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1990A&A...239..205A&db_key=AST
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Membership of Cepheids and red giants in 8 open clusters - NGC 129, 6067, 6087, 6649, 6664, IC 4725, LY 6, RU 79
The membership of eight cluster Cepheids,DL Cas,EV Sct, V367 Sct, S Nor,TW Nor,V340 Nor, U Sgr and CS Vel, has been examined by comparing theirsystemic radial velocity with that observed for the red giants in thesame clusters. The membership is very probable in seven cases, theonly-exception being CS Vel. Additional observations of main sequencestars are necessary to confirm some of the conclusions. Onespectroscopic binary was discovered among the Cepheids (DL Cas) and atleast four were among the red giants. Orbits have been determined fortwo red giants, one in NGC 129 and one in IC 4725. The position withinthe instability strip of the nonvariable F5Ib star in NGC 129 is due toits probable composite (gK + dB) character. The ratio of the number ofCepheids to the number of red giants is less than 1, in good agreementwith the prediction of evolutionary models with core overshooting. Thisstudy is based on 382 observations of 45 stars, obtained with the radialvelocity scanner CORAVEL.
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The binary Cepheid DL CAS and the open cluster NGC 129
The Cepheid DL Cas and the nonvariable supergiant Star A are confirmedas members of NGC 129, and both are found to be spectroscopic binarieswith orbital periods of a few years. Periods and orbits are determinedfor both stars. Star A is apparently rotating; tidal interaction withits companion is discussed and then rejected as the probable cause ofthe rotation. The membership of other stars and the velocity of thecluster are redetermined.
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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.
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Observational studies of Cepheids. II - BVRI photometry of 112 Cepheids
Over 4000 differentially determined photoelectric BVRI observations andthe resulting light curves are presented for 112 Cepheids accessiblefrom Northern Hemisphere observatories. The internal precision of thesedata is better than + or - 0.01 mag, and the accuracy of transformationto the Johnson BVRI system is nearly as good.
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Comparative studies of young open clusters. III - Empirical isochronous curves and the zero age main sequence
A complete set of empirical isochronous curves is presented for 14groups of open clusters younger than the Hyades. The U-B/B-V relationand the ZAMS have been reexamined, and the present results confirm thesequence of Blaauw (1963) while contradicting the revision proposed byEggen (1976). Absolute ages for each age group have been obtained froman age calibration based on a new grid of evolutionary models by Maeder(1981). Stellar evolution in the red giant region is discussed.
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Evolved stars in open clusters.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976ApJS...30..451H&db_key=AST
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(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
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Astrometric investigations of galactic clusters. I. NGC 129.
Abstract image available at:http://adsabs.harvard.edu/abs/1961AJ.....66...16L
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Überriesen FO-K7 Ia-II in galaktischen Sterhaufen. I. Mittelung von: Leuchtkraft, Alter und Eigenfarben galaktischer Überriesen. Mit 3 Textabbildungen
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Dreifarben-Photometrie einer Sternhaufengruppe in der Cassiopeia (NGC 103, NGC 129, NGC 136, NGC 146, K 14, und K 16)
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Cepheids in Galactic Clusters.IV. DL CAS in NGC 129.
Abstract image available at:http://adsabs.harvard.edu/abs/1959ApJ...130...80A
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Cepheids in Galactic Clusters. II Radial Velcocities and Spectral Types in NGC 129, NGC 6664, and NGC 7790.
Abstract image available at:http://adsabs.harvard.edu/abs/1958ApJ...128..161K
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