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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Binary Star Speckle Interferometry: Measurements and Orbits
Results of our second observational run of binary star interferometricmeasurements with an ICCD speckle camera attached to the 1.52 mtelescope of the Observatorio Astronómico Nacional at Calar Alto(Almería, Spain) in 2000 June-July are presented. The measuredangular separations range from 0.096" to 6.558". With the use of the newspeckle data, the orbits of the visual binaries WDS 14369+4813 and WDS21597+4908 are improved.
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Statistics of spectroscopic sub-systems in visual multiple stars
A large sample of visual multiples of spectral types F5-M has beensurveyed for the presence of spectroscopic sub-systems. Some 4200 radialvelocities of 574 components were measured in 1994-2000 with thecorrelation radial velocity meter. A total of 46 new spectroscopicorbits were computed for this sample. Physical relations are establishedfor most of the visual systems and several optical components areidentified as well. The period distribution of sub-systems has a maximumat periods from 2 to 7 days, likely explained by a combination of tidaldissipation with triple-star dynamics. The fraction of spectroscopicsub-systems among the dwarf components of close visual binaries withknown orbits is similar to that of field dwarfs, from 11% to 18% percomponent. Sub-systems are more frequent among the components of widevisual binaries and among wide tertiary components to the known visualor spectroscopic binaries - 20% and 30%, respectively. In triple systemswith both outer (visual) and inner (spectroscopic) orbits known, we findan anti-correlation between the periods of inner sub-systems and theeccentricities of outer orbits which must be related to dynamicalstability constraints. Tables 1, 2, and 6 are only available inelectronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/382/118
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Kinematics of Hipparcos Visual Binaries. II. Stars with Ground-Based Orbital Solutions
This paper continues kinematical investigations of the Hipparcos visualbinaries with known orbits. A sample, consisting of 804 binary systemswith orbital elements determined from ground-based observations, isselected. The mean relative error of their parallaxes is about 12% andthe mean relative error of proper motions is about 4%. However, even 41%of the sample stars lack radial velocity measurements. The computedGalactic velocity components and other kinematical parameters are usedto divide the stars with known radial velocities into kinematical agegroups. The majority (92%) of binaries from the sample are thin diskstars, 7.6% have thick disk kinematics and only two binaries have halokinematics. Among them, the long-period variable Mira Ceti has a verydiscordant {Hipparcos} and ground-based parallax values. From the wholesample, 60 stars are ascribed to the thick disk and halo population.There is an urgent need to increase the number of the identified halobinaries with known orbits and substantially improve the situation withradial velocity data for stars with known orbits.
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Binary star speckle measurements at Calar Alto. I.
We present the first results of our speckle interferometric measurementsof binary stars made with the ICCD speckle camera using the 1.52-mtelescope of the Observatorio Astronomico Nacional at Calar Alto (Spain)in September, 1999. The data contain 123 observations of 83 systems. Themeasured angular separations range from 0farcs153 to 6farcs727 . We haveused there new speckle measurements to improve the orbital elements forthe binaries COU 247 and BU 524 AB.
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ICCD Speckle Observations of Binary Stars. XXIII. Measurements during 1982-1997 from Six Telescopes, with 14 New Orbits
We present 2017 observations of 1286 binary stars, observed by means ofspeckle interferometry using six telescopes over a 15 year period from1982 April to 1997 June. These measurements constitute the 23dinstallment in CHARA's speckle program at 2 to 4 m class telescopes andinclude the second major collection of measurements from the MountWilson 100 inch (2.5 m) Hooker Telescope. Orbital elements are alsopresented for 14 systems, seven of which have had no previouslypublished orbital analyses.
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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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Observations of Double Stars and New Pairs. XVII.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJS..105..475H&db_key=AST
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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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Stroemgren photometry of F- and G-type stars brighter than V = 9.6. I. UVBY photometry
Within the framework of a large photometric observing program, designedto investigate the Galaxy's structure and evolution, Hβ photometryis being made for about 9000 stars. As a by-product, supplementary uvbyphotometry has been made. The results are presented in a cataloguecontaining 6924 uvby observations of 6190 stars, all south ofδ=+38deg. The overall internal rms errors of one observation(transformed to the standard system) of a program star in the interval6.5
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Measurements of close binaries performed at PIC DU Midi
A total of 241 measurements of 119 close binaries observed with the 2-mTelescope Bernard Lyot at Pic du Midi Observatory are given. Themeasurements were performed with a micrometer with illuminated wires.
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Binary-star measurements carried out at PIC DU Midi and at Nice
Data on 219 measurements of 103 close binaries observed with the 2mtelescope at Pic du Midi are presented. Also presented are data on 230measurements of 126 binaries observed with the 74 cm refractor of theNice Observatory.
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Observations of double stars and new pairs. XIV
Results of a continuing survey of visual double stars are presented,including 4880 measurements made from February 1987 to November 1989.The positions in WDS format and Durchmusterung numbers are given for 194pairs first reported here. Micrometer measurements of 1142 doubles madewith the Swarthmore 61 cm refractor are presented. Magnitudes areestimated for some of the objects. Plate measurements, plateorientations, position angles, number of nights, and measured exposuresare given. Visual observations of 342 pairs obtained in May 1989 atCerro Tololo, mostly with the 1.0 m reflector, are reported.
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ICCD speckle observations of binary stars. III - A survey for duplicity among high-velocity stars
An analysis of speckle interferometry data for 182 stars has resulted inthe detection of 10 binaries, four of which are newly resolved systems.After correcting for selection effects, the data are found to becompatible with a total frequency for high-velocity long-period doubleswhich is as large as that for low-velocity stars. Based on spectroscopicparallaxes and visual magnitudes, these binaries are found to be within100 pc of the sun, with eight having linear separations of less than 20AU. Four of the binaries are determined to have periods of less than 20yr.
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Micrometer Measurements of Visual Double Stars - Part Three -
Not Available
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Interferometric observations of double stars in 1983 and 1984
Position angles and separations of visual binary stars have beenmeasured with a photoelectric phase-grating interferometer on the 1-mreflector on Mt. Sanglok. The observational technique is brieflydescribed. The 134 measurements of 123 pairs with rho of between 0.05and 0.07 arcsec and the residuals from the ephemerides are given. HR 813= Mu Cet has been resolved interferometrically for the first time.
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Micrometer Measures of Double Stars at Lick Observatory
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984PASP...96..174C&db_key=AST
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Orbits for 44 visual binaries
A tabulation is presented of revised orbital elements, calculated for 44visual binary stars from published data together with new observations.All of the newly calculated orbits show smaller departures from theobservations than older determinations, and in many cases the systematictime dependence of the (O-C)(theta), (O-C)rho residuals is found tovanish.
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Micrometer Observations of Double Stars and New Pairs - Part Ten
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980ApJS...44..111H&db_key=AST
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Double star measures at Lick Observatory Mount Hamilton California.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976PASP...88..325H&db_key=AST
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Micrometer observations of double stars.8.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975ApJS...29..315H&db_key=AST
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Micrometric Measures of Double Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974ApJS...28..413V&db_key=AST
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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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A Search for Metal-Deficient Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJS...22..117B&db_key=AST
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MK Classification of 142 Visual Binaries
Not Available
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The masses of stars above the main sequence.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969AJ.....74..689S&db_key=AST
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Distances fondamentales d'etoiles doubles serrees.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969A&A.....2..126C&db_key=AST
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Mesures d'etoiles doubles faites a Nice a la lunette de 50 cm.
Not Available
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Mikrometermessungen von Doppelsternen. VI.
Not Available
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Mesures d'etoiles doubles faites AU 38cm de l'Observatoire de Paris.
Not Available
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INHABITED SKY
