The Geneva-Copenhagen survey of the Solar neighbourhood. Ages, metallicities, and kinematic properties of 14 000 F and G dwarfs
We present and discuss new determinations of metallicity, rotation, age,kinematics, and Galactic orbits for a complete, magnitude-limited, andkinematically unbiased sample of 16 682 nearby F and G dwarf stars. Our63 000 new, accurate radial-velocity observations for nearly 13 500stars allow identification of most of the binary stars in the sampleand, together with published uvbyβ photometry, Hipparcosparallaxes, Tycho-2 proper motions, and a few earlier radial velocities,complete the kinematic information for 14 139 stars. These high-qualityvelocity data are supplemented by effective temperatures andmetallicities newly derived from recent and/or revised calibrations. Theremaining stars either lack Hipparcos data or have fast rotation. Amajor effort has been devoted to the determination of new isochrone agesfor all stars for which this is possible. Particular attention has beengiven to a realistic treatment of statistical biases and errorestimates, as standard techniques tend to underestimate these effectsand introduce spurious features in the age distributions. Our ages agreewell with those by Edvardsson et al. (\cite{edv93}), despite severalastrophysical and computational improvements since then. We demonstrate,however, how strong observational and theoretical biases cause thedistribution of the observed ages to be very different from that of thetrue age distribution of the sample. Among the many basic relations ofthe Galactic disk that can be reinvestigated from the data presentedhere, we revisit the metallicity distribution of the G dwarfs and theage-metallicity, age-velocity, and metallicity-velocity relations of theSolar neighbourhood. Our first results confirm the lack of metal-poor Gdwarfs relative to closed-box model predictions (the ``G dwarfproblem''), the existence of radial metallicity gradients in the disk,the small change in mean metallicity of the thin disk since itsformation and the substantial scatter in metallicity at all ages, andthe continuing kinematic heating of the thin disk with an efficiencyconsistent with that expected for a combination of spiral arms and giantmolecular clouds. Distinct features in the distribution of the Vcomponent of the space motion are extended in age and metallicity,corresponding to the effects of stochastic spiral waves rather thanclassical moving groups, and may complicate the identification ofthick-disk stars from kinematic criteria. More advanced analyses of thisrich material will require careful simulations of the selection criteriafor the sample and the distribution of observational errors.Based on observations made with the Danish 1.5-m telescope at ESO, LaSilla, Chile, and with the Swiss 1-m telescope at Observatoire deHaute-Provence, France.Complete Tables 1 and 2 are only available in electronic form at the CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/418/989
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Two-colour photometry for 9473 components of close Hipparcos double and multiple stars
Using observations obtained with the Tycho instrument of the ESAHipparcos satellite, a two-colour photometry is produced for componentsof more than 7 000 Hipparcos double and multiple stars with angularseparations 0.1 to 2.5 arcsec. We publish 9473 components of 5173systems with separations above 0.3 arcsec. The majority of them did nothave Tycho photometry in the Hipparcos catalogue. The magnitudes arederived in the Tycho B_T and V_T passbands, similar to the Johnsonpassbands. Photometrically resolved components of the binaries withstatistically significant trigonometric parallaxes can be put on an HRdiagram, the majority of them for the first time. Based on observationsmade with the ESA Hipparcos satellite.
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The contact binary AW Ursae Majoris as a member of a multiple system
New and published UBV photoelectric and spectroscopic observations of AWUMa are analyzed and interpreted by a triple or quadruple-star model.The derived inclination angle i = 78.3°, the photometric mass ratioq = 0.08 as well as all available radial velocities, corrected for thesystemic velocity changes, were used to determine the masses of thecomponents of the contact binary as M_1 = (1.79+/-0.14) Msunand M_2 = (0.143+/-0.011) Msun. These values set the binaryon the ZAMS. Variations in the systemic velocity suggest the existenceof a third body on a P_3 = 398 days orbit with eccentricity e_3 =0.227+/-0.056. Assuming that the orbits of the contact binary and of thethird body are coplanar, its mass is M_3 = (0.85+/-0.13)Msun. The long-term orbital period decrease is explained bymass transfer from the more massive to the less massive componentaccompanied by the angular momentum loss due to mass outflow from theouter Lagrangian point L2. The period decrease occurredeither suddenly (in two period jumps 6200 days apart) or continuously.In the second case, the (O-C) residuals from the parabolic fit can beexplained by the light-time effect caused by a fourth body on a P_4 =6250 days eccentric orbit (e_4 = 0.63+/-0.24). For the most probablerange of inclination of the possible fourth component orbit 60°>i_4> 40°, the range of its mass is 0.168Msun
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Micrometer Measures of Double Stars
Micrometer measures of 795 double stars made with the 26 inch (0.66 m)refractor of the US Naval Observatory from 1984 to 1990 are presented.
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Sudden Period Change in the Contact Binary AW UMa?
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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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BVRIJHK photometry of RR Lyrae variables
BVRI and JHK photometry are presented for the PR Lyrae variables SWAndromedae and TU Ursae Majoris. BVRI photometry is also presented forthe TT Lyncis and T Sextantis variables and two JHK points for UUVirginis. These 331 observations can be phase-locked to radialvelocities given by Barnes et al. (1988) and by Wilson et al. (1989).Attention is also given to new observations of TU UMa in the context ofthe binary model proposed by Saha and White (1990).
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AW UMa is in Active Phase of Mass Transfer
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I.A.U. Archives of Unpublished Observations of Variable Stars - 1979-1981 Data
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Visual multiples. VII - MK classifications
Classifications are given for 865 components of visual multiples; theyshow no systematic differences from the MK system, and the random errorsare one subclass in type and two-thirds of a luminosity class. It isfound that at least 1% of the F-type IV and V stars are weak-lined, 32%of the A4-F1 IV and V stars are Am, and 5% of the A0-A3 IV and V starsare early-type Am. Attention is called to the large fraction (55%) ofthe A3-A9 III-V stars that are of luminosity classes III or IV, unlikethe percentage (16%) at neighboring types.
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Mesures d'étoiles doubles faites à l'équatorial de 38 CM de l'Observatoire de Paris
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972A&AS....6..147B&db_key=AST
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Mesures d'étoiles doubles faites à Nice aux lunettes de 50 et de 74 CM
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970A&AS....3...51C&db_key=AST
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MK classifications for F and G-type stars. I.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969AJ.....74..916H&db_key=AST
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Mesures d'etoiles doubles faites AU 38cm de l'Observatoire de Paris.
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The Light Variation of the Eclipsing Binary BD +30°2163
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BD +30 2163, a new W UMa variable.
Abstract image available at:http://adsabs.harvard.edu/abs/1964AJ.....69..124P
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Mesures d'étoiles doubles faites au 0,38 m de l'Observatoire de Paris.
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Measures of 313 doubles stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963AJ.....68..114W&db_key=AST
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Mesures d'étoiles doubles faites au réfracteur de 38 cm de l'Observatoire de Nice
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La mesure des vitesses radiales au prisme objectif - X - 4e liste de vitesses radiales déterminées au prisme objectif à vision directe
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Mesures d'étoiles doubles effectuées au réfracteur de 38 cm de l' Observatoire de Nice
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Mesures d'Etoiles Doubles faites à l'Observatoire de Paris (suite)
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Bergedorfer Spektral-Durchmusterung der 115 noerdlichen Kapteynschen Eichfelder+Bd.3: Eichfeld 44 bis 67, Deklination +30 deg.
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INHABITED SKY
