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A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun
Traditionally, runaway stars are O- and B-type stars with large peculiarvelocities. We would like to extend this definition to young stars (upto ?50 Myr) of any spectral type and to identify those present in theHipparcos catalogue by applying different selection criteria, such aspeculiar space velocities or peculiar one-dimensional velocities.Runaway stars are important for studying the evolution of multiple starsystems or star clusters, as well as for identifying the origins ofneutron stars. We compile the distances, proper motions, spectral types,luminosity classes, V magnitudes and B-V colours, and we utilizeevolutionary models from different authors to obtain star ages. We studya sample of 7663 young Hipparcos stars within 3 kpc from the Sun. Theradial velocities are obtained from the literature. We investigate thedistributions of the peculiar spatial velocity and the peculiar radialvelocity as well as the peculiar tangential velocity and itsone-dimensional components and we obtain runaway star probabilities foreach star in the sample. In addition, we look for stars that aresituated outside any OB association or OB cluster and the Galactic planeas well as stars for which the velocity vector points away from themedian velocity vector of neighbouring stars or the surrounding local OBassociation/cluster (although the absolute velocity might be small). Wefind a total of 2547 runaway star candidates (with a contamination ofnormal Population I stars of 20 per cent at most). Thus, aftersubtracting these 20 per cent, the runaway frequency among young starsis about 27 per cent. We compile a catalogue of runaway stars, which isavailable via VizieR.
| Red giants in open clusters. XIV. Mean radial velocities for 1309 stars and 166 open clusters
Context: Radial velocities have proved to be an efficient method formembership determination if there are at least 2 or 3 red giants in acluster. They are necessary for galactic studies, but are still missingfor many open clusters. Aims: We present the final catalogues of along-term observing programme performed with the two coravelspectrovelocimeters for red giants in open clusters. The main aims wereto detect spectroscopic binaries and determine their orbital parameters,determine the membership, and compute mean velocities for the stars andopen clusters. Methods: We computed weighted mean radial velocities for1309 stars from 10 517 individual observations, including the systemicradial velocities from spectroscopic orbits and for cepheids. Results:The final results are contained in three catalogues collecting 10 517individual radial velocities, mean radial velocities for 1309 redgiants, and mean radial velocities for 166 open clusters among whichthere are 57 new determinations. We identified 891 members and 418non-members. We discovered a total of 288 spectroscopic binaries, amongwhich 57 are classified as non-members. In addition 27 stars were judgedto be variable in radial velocities and they are all red supergiants. Conclusions: The present material, combined with recent absolute propermotions, will permit various investigation of the galactic distributionand space motions of a large sample of open clusters. However, thedistance estimates still remain the weakest part of the necessary data.This paper is the last one in this series devoted to the study of redgiants in open clusters based on radial velocities obtained with thecoravel instruments.Based on observations collected at the Haute-Provence Observatory(France) and on observations collected with the Danish 1.54-m telescopesat the European Southern Observatory, La Silla, Chile. Full Tables [seefull textsee full textsee full textsee full textsee full text] to [seefull textsee full textsee full textsee full textsee full text] are onlyavailable and Tables [see full textsee full textsee full textsee fulltextsee full text] and [see full textsee full textsee full textsee fulltextsee full text] are also available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/485/303
| Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
| SB9: The ninth catalogue of spectroscopic binary orbits
The Ninth Catalogue of Spectroscopic Binary Orbits(http://sb9.astro.ulb.ac.be) continues the series of compilations ofspectroscopic orbits carried out over the past 35 years by Batten andcollaborators. As of 2004 May 1st, the new Catalogue holds orbits for2386 systems. Some essential differences between this catalogue and itspredecessors are outlined and three straightforward applications arepresented: (1) completeness assessment: period distribution of SB1s andSB2s; (2) shortest periods across the H-R diagram; (3)period-eccentricity relation.
| 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
| UBV photometric study and basic parameters of the southern open cluster NGC 2539
We present UBV photoelectric observations of 345 stars in the field ofthe southern open cluster NGC 2539. The analysis of these data allows todetermine that 169 stars are probable members of the cluster mainsequence, while 23 are possible members. The CC and CM diagrams reveal awell-defined main sequence and a populous red giant branch. We derive areddening E(B-V) = 0.06 and an apparent distance modulus V-M_v = 10.60,equivalent to a distance of 1210 pc. The age, determined by fittingisochrones computed by the Geneva group with mass loss and moderate coreovershooting, turns out to be 630 Myr, which places this cluster withinthe Hyades-age group. The isochrone for log t = 8.80 reproduces well themorphology of the upper main sequence band in the two CM diagrams,including the binary ridge. Although this isochrone also reproduces wellthe general shape of the observed red giant pattern, it appears to be alittle too bright and too red. This fact could be probably due to theuncertainty on the exact value of the mixing-length parameter. However,mass loss during the evolution of the red giants might also partiallyaccount for their location in the HR diagram. The low contamination ofthe upper main sequence of the cluster CM diagrams and its populated redgiant branch makes NGC 2539 a very good target for testing oftheoretical models. Based on observations made at Las CampanasObservatory (Chile) and at European Southern Observatory, La Silla(Chile). Table 1 is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Red giants in open clusters. I - Binarity and stellar evolution in five Hyades-generation clusters: NGC 2447, 2539, 2632, 6633, and 6940
The present analysis for membership-determination and binary-detectionof radial velocity observations for 62 red giant stars in the HyadeslikeNGC 2447, 2539, 2632, 6633, and 6940 open clusters has yielded a binarypercentage of the order of 25-33 percent. Twelve orbits have beendetermined, and two triple systems identified. At least nine of the tenstars found in the Hertzsprung gap are composite binaries of the (gK +dA) type; the radial velocity dispersion in each cluster is close to thevalue expected on the basis of the virial theorem, assuming typicalvalues of the total mass of 1000 solar masses, and of a half-mass radiusof 3 pc.
| Photometric and Objective Prism Observations in Three Galactic Clusters.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1961ApJ...134..602P&db_key=AST
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