Adaptive Optics Observations of the Binary Star HD 43587
We present adaptive optics observations of HD 43587, one of the primarytargets of the COROT (Convection, Rotation, and Planetary Transits)asteroseismology and planet-finding space mission and a star that waspreviously detected as a spectroscopic binary by Vogt and coworkers. Weresolve a close companion, which is responsible for the radial velocityvariations of the primary. Our observations over a 3 year intervalmeasure the orbital displacement of the companion. Combining thesemeasurements with the radial velocity data of Vogt and coworkers, wesolve for the three-dimensional orbit of the system and deriveindividual masses for HD 43587 and its companion. This is particularlyinteresting in the perspective of the upcoming COROT mission. Theseobservations were part of a preparatory program for COROT, in which weobserved all COROT potential primary targets and some of its secondarytargets with adaptive optics. The majority of these stars have potentialcompanions in a 30" field. Most of these are probably backgroundobjects, but some are found within a few arcseconds of the COROT targetsand are likely to be true physical companions.Based on observations obtained at the Canada-France-Hawaii Telescope,which is operated by the National Research Council of Canada, theInstitut National des Science de l'Univers of the Centre National de laRecherche Scientifique of France, and the University of Hawaii.
|
Composite M V versus (V-I) 0 Diagram for Template Open Clusters
New CCD VI photometric data for 10 template open clusters withaccurately determined fundamental parameters are presented. From theobserved V versus V - I diagrams of the clusters, fiducial sequenceshave been defined and transformed into the Mv versus (V - I)0 diagram byaveraging sequences of template open clusters with similar ages. Theresulting composite Mv versus (V - I)0 diagram presents a homogeneousset of empirical isochrones in the age range between 5 Myr and 4 Gyr.These empirical isochrones show an overall very good agreement withthose computed from stellar evolutionary models. Theoretical isochroneswith moderate overshooting fit the observed main sequences better thanthe canonical ones for clusters older than 600 Myr. The present set ofempirical isochrones will be useful for the study of faint reddened openclusters
|
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.
|
The late A-type stars - Refined MK classification, confrontation with Stromgren photometry, and the effects of rotation
The MK spectral classification for late A-type stars is refined and theeffects of rotation of spectral classification and uvby(beta) photometryfor these stars are examined. It is found that, for A3 stars, the4417/4481 A wavelength ratio produces results that are inconsistent withthe Stark broadening of the H lines. It is suggested that this ratio isnot useful as a luminosity criterion at any spectral type.Self-consistent sequences of narrow- and broadline standards areestablished. The results of the refined classification system arecompared with Stromgren photometry, showing a set of low-v sin i A-typestars with anomalously large delta(c1) indices for theirluminosity types. It is proposed that these stars are rapid rotatorsseen at fairly low inclination angles.
|
Galactic cluster star radial velocities obtained with a focal reducer field spectrograph. I - The clusters IC 1805, NGC 2287, NGC 2548, IC 4665, NGC 6633, NGC 6940 and NGC 7092
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&AS...62..301G&db_key=AST
|
Spectral types in the open cluster NGC 6633
Spectral types are given for the 26 brightest stars in the region of NGC6633. Only two of the giants are definitely cluster members. Twoapparent blue stragglers are present, as well as one extreme Ap star,four marginal Am stars, and two stars with weak shell lines.
|
Membership of the open cluster NGC 6633
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&AS....9..213S&db_key=AST
|
Southern open clusters II. UBV and Hbeta photometry of 11 clusters between galactic longitudes 259d and 280d
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&AS....9...97V&db_key=AST
|
Catalogue des étoiles mesurées dans le système photométrique de l'Observatoire de Genève
Not Available
|
The Galactic Cluster, NGC 6633.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1958ApJ...127..539H&db_key=AST
|
Relative proper motions of stars in the region of the open cluster NGC 6633.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1958AJ.....63..387V&db_key=AST
|
Untersuchung der offenen Sternhaufen IC 4665, NGC 6633, IC 4756
Not Available
|
