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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.
| Astrophysical supplements to the ASCC-2.5. II. Membership probabilities in 520 Galactic open cluster sky areas
We present a catalogue (CSOCA ) of stars residing in 520 Galactic opencluster sky areas which is the result of the kinematic (proper motion)and photometric member selection of stars listed in the homogeneousAll-sky Compiled Catalogue of 2.5 Million Stars (ASCC-2.5). We describethe structure and contents of the catalogue, the selection procedureapplied, and the proper motion and photometric membership constraintsadopted. In every cluster area the CSOCA contains the complete list ofthe ASCC-2.5 stars regardless of their membership probability. Forevery star the CSOCA includes accurate J2000 equatorial coordinates,proper motions in the Hipparcos system, BV photometric data in theJohnson system, proper motion and photometric membership probabilities,as well as angular distances from the cluster centers for about 166 000ASCC-2.5 stars. If available, trigonometric parallaxes, spectral types,multiplicity and variability flags from the ASCC-2.5, and radialvelocities with their errors from the Catalogue of Radial Velocities ofGalactic Stars with high precision Astrometric Data (CRVAD) are alsogiven.
| Catalogue of H-alpha emission stars in the Northern Milky Way
The ``Catalogue of Stars in the Northern Milky Way Having H-alpha inEmission" appears in Abhandlungen aus der Hamburger Sternwarte, Band XIin the year 1997. It contains 4174 stars, range {32degr <= l() II< 214degr , -10degr < b() II < +10degr } having the Hαline in emission. HBH stars and stars of further 99 lists taken from theliterature till the end of 1994 were included in the catalogue. We givethe cross-identification of stars from all lists used. The catalogue isalso available in the Centre de Données, Strasbourg ftp130.79.128.5 or http://cdsweb.u-strasbg.fr and at the HamburgObservatory via internet.
| Catalogue of stars in the Northern Milky Way having H-alpha in emission.
The catalogue contains 4174 stars in the Northern Milky Way, range32° ? lII< 214°, -10° < bII< +10°, having the H? line in emission. The HBH list (mainlist, Schmidt camera Hamburg-Bergedorf, red plates taken in the years1964-70) contains 1979 objects partly identical with those in otherlists of H? emission-line stars given in the literature up till1994. Non-stellar objects (e.g. H II regions, planetary nebulae) havenot been included in this catalogue except for those objects containingcentral stars which have the H? line in emission, and also forsome doubtful cases. In Part 1 the authors give the equatorial (2000.0)and galactic coordinates, the brightness and the spectrum (if existingin the literature), the membership of HBH, the estimation of continuumand H?-line intensity, the reference to the finding chart in Part2 and the cross-identification of 100 lists mostly of H? emissionline stars. In Part 2 the authors present the finding charts for morethan half of the objects; they have the "normal" orientation and mainlysize 7 arcmin square. At the end they give elementary statistics of thepresent data showing also gaps in the material.
| Variability of Two Supergiants: HD 3940 and HD 10494
Not Available
| A spectral survey of early-type stars in the region of Cassiopeia using an objective prism
Not Available
| New Emission Stars in Cassiopeia
Not Available
| Second Supplement to the Mount Wilson Catalogue and Bibliography of Stars of Classes B and a whose Spectra have Bright Hydrogen Lines.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1949ApJ...110..387M&db_key=AST
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