Spectroscopic study of the open cluster Blanco 1
Aims: As a part of our program on binaries in open clusters, we presenta spectroscopic study of the bright stars of Blanco 1 aimed at detectingand characterizing spectroscopic binaries. Methods: Forty fivestars previously mentioned as cluster candidates, plus another 24 starsin a wider region around the cluster were observed repeatedly during 6years, with a spectral resolving power 13 300. Radial velocities weremeasured by cross-correlations. Results: We obtained a meancluster velocity of 6.2 ± 0.3 km s-1 and determinedkinematic membership. Eleven spectroscopic binaries were detected, andorbital solutions are presented for eight of them. Six binaries areconfirmed to be members of the cluster. All of them are single-linedspectroscopic systems with periods in the range 1.9-1380 days.Considering all suspected binaries, the cluster binary frequency amountsto about 50%.Based on observations obtained at the Complejo Astronómico ElLeoncito (CASLEO), Argentina.
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Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
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H? kinematics of a z~ 1 disc galaxy from near-infrared integral field spectroscopy
In this Letter we present the first 3D spectroscopic study of H?emission in a z~ 1 field galaxy with an integral field unit. Using theCambridge Infrared Panoramic Survey Spectrograph (CIRPASS) onGemini-South, we map the spatial and velocity distribution of H?emission in the z= 0.819 galaxy CFRS 22.1313. We detect two H?emitting regions with a velocity separation of 220 +/- 10kms-1. Combining the 2D map of H? emission with HubbleSpace Telescope F814W imaging, we determine a lower limit of 180 +/- 20kms-1 for the rotation velocity of this MB(rest)~-21 galaxy. We note that our value is significantly higher than therotation velocity of 120 +/- 10 kms-1 reported by Barden etal. for their long-slit spectroscopic study of this galaxy. Our lowerlimit on the rotation velocity is entirely consistent with no evolutionof the rest B-band Tully-Fisher relation. The position of this galaxyrelative to the mean rest B-band Tully-Fisher relation of Pierce &Tully is consistent with brightening of no more than ~1mag at z= 0.8. Alarger integral field unit sample, without the uncertainties inherent tolong-slit samples, is needed to determine the evolution of theTully-Fisher relation accurately out to z~ 1.
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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 young cluster Blanco 1
We present spectroscopic observations of some 115 stars of the clusterBlanco 1, extending from the Ca II(H,K) region to the Ca II(I-R)triplet, supporting an age similar to that of the young cluster alphaPersei. The H-alpha absorption equivalent with vs (B - V) diagram formsa well-defined locus, with decreasing absorption equivalent width fordecreasing effective temperature, akin to solar neighborhood dwarfs. Alarge spread in the Ca II surface flux, as a function of (B - V), alsoindicates the presence of a high degree of surface inhomogeneity,synonymous with high magnetic activity in young stars. A drop-off in theCa II flux at (B - V) = 1.0 is also similar to the solar neighborhoodstars, and shows that the primary chromospheric cooling changes from theCa II and Mg II lines to the Balmer lines. The mean chromospherictemperature for stars at 4800 K lies between 8000 K and 10,000 K, basedon theoretical models, which is somewhat higher than the older solarneighborhood dwarfs. The high mean Ca II surface flux of the sample isalso consistent with that of other young clusters. We were able tomeasure the equivalent width of the Li(6708) line, whose strength as afunction of (B - V) indicates an age similar to the young cluster alphaPersei. The lithium abundance decreases with decreasing effectivetemperature, consistent with the premise of lithium depletion in starswith larger convection zones. Using published photometry and a recentZero Age Main Sequence (ZAMS) fitting method, we also re-define thedistance to the cluster to be 246 pc.
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Liste des étoiles Ap et Am dans les amas ouverts (édition révisée)
Not Available
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Liste des étoiles Ap et Am dans les amas ouverts (Edition révisée)
Not Available
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Catalog of AP and AM stars in open clusters
The previous results of Raab (1922), Markarian (1951), and Collinder(1931) have been used to catalog Ap and Am stars that are in the fieldof open clusters. Tabular data are presented for the clusterdesignation, the HD or HDE number, the right ascension (1900), thedeclination (1900), and the magnitude. Also listed are the spectraltypes and, for certain stars, the probability of cluster membership.
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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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Chemically peculiar stars in open clusters. I - The catalog
The largest existing compilation is presented of Ap and Am open clusterstars. The catalog contains information on 381 chemically peculiar (CP)stars of the upper main sequence in 79 open clusters. The catalog iscomposed of the following tables: (1) the main body, which lists CP (orsuspected CP) stars which are kinematical (or suspected kinematical)members of open clusters; (2) the list of CP (or suspected CP) starssometimes numbered among cluster members but which are actuallykinematical nonmembers; (3) the list of stars sometimes designated as'peculiar' but, in fact, probably not CP; (4) references for numberingsystems of cluster stars; (5) references for membership; and (6)references for spectral and/or peculiarity types.
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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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Bibliographic Catalogue of Stellar Radical Velocities
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1986A&AS...65...59B&db_key=AST
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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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Stellar kinematics and evolution
Not Available
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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
