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HD 195850


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Contribution to the study of F-G-K-M binaries: XII. Orbital elements of seven new spectroscopic binaries
The orbital elements of seven single-lined spectroscopic binaries, HD31855, HD 59643, HD 60092, HD 133189, HD 162262, HD 203522, BD+43o 1331 are presented. They are obtained from observationsmade with two photoelectric spectrometers of CORAVEL type, the firstlocated at the Observatoire de Haute-Provence and the second at theCambridge Observatories. From those orbital elements and other dataavailable in the literature, we deduce some information about the unseencompanions and their separations with respect to the primaries. We thendiscuss the rotation-revolution synchronism and conclude that some ofthose stars have probably reached the state of (pseudo-)synchronism.Finally we give a synopsis of the results obtained in this series ofpapers. Our radial velocity monitoring of more than three decades hasallowed us to derive accurate orbital elements of 35 spectroscopicbinaries, with a cool primary star of type F-G-K-M. The correspondingrange of periods varies from a few days to more than 10 years.

Pulkovo compilation of radial velocities for 35495 stars in a common system.
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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. Our˜63 000 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

Contribution à l'étude des binaires des types F, G, K, M. VIII. HD 195850 et HD 201193, binaires spectroscopiques à raies doubles Contribution to the study of F, G, K, M binaries. VIII. HD 195850 and HD 201193, double-lined spectroscopic binaries
Radial-velocity observations of the double-lined spectroscopic binariesHD 195850 and HD 201193 have been carried out at the Observatoire deHaute-Provence with the CORAVEL instrument in order to determine theirorbital elements. They are as follows HD 195850: P = 37.94106 days; T =2444872.24 HJD; omega = 111o 5 ; e = 0.185; K_1 = 34.15 kms-1; K_2 = 44.72 km s-1; V_0 = 0.75 Kms-1; a_1 sin i = 17.51 Gm; a_2 sin i = 22.93 Gm; M_1 sin3i = 1.04 M_sun; M_2 sin 3i = 0.79 M_sun. HD201193: P = 22.299540 days; T = 2448137.004 HJD; omega = 144o7; e = 0.388; K_1 = 54.15 km s-1; K_2 = 54.77 kms-1; V_0 = - 13.01 km s-1; a_1 sin i = 15.31 Gm;a_2 sin i = 15.48 Gm; M_1 sin 3i = 1.179 M_sun; M_2 sin3i = 1.165 M_sun. For HD 195850, we propose a F5V + G2V modelon the basis of both the Hipparcos-measured parallax and the Delta m_vvalue, 1.1 mag, deduced from the intensities of the correlation dips. HD201193, for its part, is formed by two quasi-identical F6V stars.Strömgren photometric indices suggest the following physicalparameters: M_v = 3.6 ; T_eff = 6200 K; log g = 4.2. Using\cite[Schaller et al. (1992)]{S92} evolutionary tracks for stars ofsolar metallicity, we estimate M = 1.25 M_sun for the mass of eachcomponent. This system should be somewhat evolved above the ZAMS, andthe possibility of eclipses is, a priori, not excluded; it is likelythat the components rotate in synchronism with the orbital motion.

The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle
The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.

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.

A. de Sitter's photographic polar photometry revisited; some remarks on photographic photometry with objective gratings
Not Available

Radial Velocities, Spectral Types, and Luminosity Classes of 820 Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1950ApJ...112...48M&db_key=AST

Photographic magnitudes of stars brighter than 7m.75 between +75° and +80° declination (Errata: 11 270)
Not Available

Yerkes actinometry. Zone +73deg to +90deg.
Not Available

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Observation and Astrometry data

Constellation:りゅう座
Right ascension:20h20m43.71s
Declination:+82°22'05.0"
Apparent magnitude:7.031
Distance:54.407 parsecs
Proper motion RA:10.3
Proper motion Dec:-43.6
B-T magnitude:7.581
V-T magnitude:7.077

Catalogs and designations:
Proper Names   (Edit)
HD 1989HD 195850
TYCHO-2 2000TYC 4597-1505-1
USNO-A2.0USNO-A2 1650-02262270
HIPHIP 100321

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