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# HD 158837

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 Astrometric orbits of SB^9 starsHipparcos Intermediate Astrometric Data (IAD) have been used to deriveastrometric orbital elements for spectroscopic binaries from the newlyreleased Ninth Catalogue of Spectroscopic Binary Orbits(SB^9). This endeavour is justified by the fact that (i) theastrometric orbital motion is often difficult to detect without theprior knowledge of the spectroscopic orbital elements, and (ii) suchknowledge was not available at the time of the construction of theHipparcos Catalogue for the spectroscopic binaries which were recentlyadded to the SB^9 catalogue. Among the 1374 binaries fromSB^9 which have an HIP entry (excluding binaries with visualcompanions, or DMSA/C in the Double and Multiple Stars Annex), 282 havedetectable orbital astrometric motion (at the 5% significance level).Among those, only 70 have astrometric orbital elements that are reliablydetermined (according to specific statistical tests), and for the firsttime for 20 systems. This represents a 8.5% increase of the number ofastrometric systems with known orbital elements (The Double and MultipleSystems Annex contains 235 of those DMSA/O systems). The detection ofthe astrometric orbital motion when the Hipparcos IAD are supplementedby the spectroscopic orbital elements is close to 100% for binaries withonly one visible component, provided that the period is in the 50-1000 drange and the parallax is >5 mas. This result is an interestingtestbed to guide the choice of algorithms and statistical tests to beused in the search for astrometric binaries during the forthcoming ESAGaia mission. Finally, orbital inclinations provided by the presentanalysis have been used to derive several astrophysical quantities. Forinstance, 29 among the 70 systems with reliable astrometric orbitalelements involve main sequence stars for which the companion mass couldbe derived. Some interesting conclusions may be drawn from this new setof stellar masses, like the enigmatic nature of the companion to theHyades F dwarf HIP 20935. This system has a mass ratio of 0.98 but thecompanion remains elusive. Synthetic Lick Indices and Detection of α-enhanced Stars. II. F, G, and K Stars in the -1.0 < [Fe/H] < +0.50 RangeWe present an analysis of 402 F, G, and K solar neighborhood stars, withaccurate estimates of [Fe/H] in the range -1.0 to +0.5 dex, aimed at thedetection of α-enhanced stars and at the investigation of theirkinematical properties. The analysis is based on the comparison of 571sets of spectral indices in the Lick/IDS system, coming from fourdifferent observational data sets, with synthetic indices computed withsolar-scaled abundances and with α-element enhancement. We useselected combinations of indices to single out α-enhanced starswithout requiring previous knowledge of their main atmosphericparameters. By applying this approach to the total data set, we obtain alist of 60 bona fide α-enhanced stars and of 146 stars withsolar-scaled abundances. The properties of the detected α-enhancedand solar-scaled abundance stars with respect to their [Fe/H] values andkinematics are presented. A clear kinematic distinction betweensolar-scaled and α-enhanced stars was found, although a one-to-onecorrespondence to thin disk'' and thick disk'' components cannot besupported with the present data. Reprocessing the Hipparcos Intermediate Astrometric Data of spectroscopic binaries. II. Systems with a giant componentBy reanalyzing the Hipparcos Intermediate Astrometric Data of a largesample of spectroscopic binaries containing a giant, we obtain a sampleof 29 systems fulfilling a carefully derived set of constraints andhence for which we can derive an accurate orbital solution. Of these,one is a double-lined spectroscopic binary and six were not listed inthe DMSA/O section of the catalogue. Using our solutions, we derive themasses of the components in these systems and statistically analyzethem. We also briefly discuss each system individually.Based on observations from the Hipparcos astrometric satellite operatedby the European Space Agency (ESA 1997) and on data collected with theSimbad database. Precision and accuracy of the orbital parameters derived from 2D & 1D space observations of visual or astrometric binariesRecent investigations (e.g. Han et al. \cite{Han-2001:a}) have shownthat fitting the Hipparcos observations with an orbital model when theastrometric wobble caused by the companion is below the noise level canhave rather unexpected consequences. With new astrometric missionscoming out within the next ten years, it is worth investigating theorbit reconstruction capabilities of such instruments at lowsignal-to-noise ratio. This is especially important because some of themwill have no input catalogue, thus meaning that all the orbitalparameters will have to be derived from scratch. The puzzling case ofalmost parabolic orbits is also investigated. The tidal effects on the lithium abundance of binary systems with giant componentWe analyse the behavior of lithium abundance as a function of effectivetemperature, projected rotational velocity, orbital period andeccentricity for a sample of 68 binary systems with giant component andorbital period ranging from about 10 to 6400 days. For these binarysystems the Li abundances show a gradual decrease with temperature,paralleling the well established result for single giants. We have alsoobserved a dependence of lithium content on rotation. Binary systemswith moderate to high rotation present also moderate to high Li content.This study shows also that synchronized binary systems with giantcomponent seem to retain more of their original lithium than theunsynchronized systems. For orbital periods lower than 100 to 250 days,typically the period of synchronization for this kind of binary systems,lithium depleted stars seems to be unusual. The suggestion is made thatthere is an inhibited zone" in which synchronized binary systems withgiant component having lithium abundance lower than a threshold levelshould be unusual. Based on observations collected at ESO, La Silla. Binary star speckle measurements during 1992-1997 from the SAO 6-m and 1-m telescopes in ZelenchukWe present the results of speckle interferometric measurements of binarystars made with the television photon-counting camera at the 6-m BigAzimuthal Telescope (BTA) and 1-m telescope of the Special AstrophysicalObservatory (SAO) between August 1992 and May 1997. The data contain 89observations of 62 star systems on the large telescope and 21 on thesmaller one. For the 6-m aperture 18 systems remained unresolved. Themeasured angular separation ranged from 39 mas, two times above the BTAdiffraction limit, to 1593 mas. A catalog of rotational and radial velocities for evolved starsRotational and radial velocities have been measured for about 2000evolved stars of luminosity classes IV, III, II and Ib covering thespectral region F, G and K. The survey was carried out with the CORAVELspectrometer. The precision for the radial velocities is better than0.30 km s-1, whereas for the rotational velocity measurementsthe uncertainties are typically 1.0 km s-1 for subgiants andgiants and 2.0 km s-1 for class II giants and Ib supergiants.These data will add constraints to studies of the rotational behaviourof evolved stars as well as solid informations concerning the presenceof external rotational brakes, tidal interactions in evolved binarysystems and on the link between rotation, chemical abundance and stellaractivity. In this paper we present the rotational velocity v sin i andthe mean radial velocity for the stars of luminosity classes IV, III andII. Based on observations collected at the Haute--Provence Observatory,Saint--Michel, France and at the European Southern Observatory, LaSilla, Chile. Table \ref{tab5} also available in electronic form at CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html Catalogs of temperatures and [Fe/H] averages for evolved G and K starsA catalog of mean values of [Fe/H] for evolved G and K stars isdescribed. The zero point for the catalog entries has been establishedby using differential analyses. Literature sources for those entries areincluded in the catalog. The mean values are given with rms errors andnumbers of degrees of freedom, and a simple example of the use of thesestatistical data is given. For a number of the stars with entries in thecatalog, temperatures have been determined. A separate catalogcontaining those data is briefly described. Catalog only available atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html A catalogue of [Fe/H] determinations: 1996 editionA fifth Edition of the Catalogue of [Fe/H] determinations is presentedherewith. It contains 5946 determinations for 3247 stars, including 751stars in 84 associations, clusters or galaxies. The literature iscomplete up to December 1995. The 700 bibliographical referencescorrespond to [Fe/H] determinations obtained from high resolutionspectroscopic observations and detailed analyses, most of them carriedout with the help of model-atmospheres. The Catalogue is made up ofthree formatted files: File 1: field stars, File 2: stars in galacticassociations and clusters, and stars in SMC, LMC, M33, File 3: numberedlist of bibliographical references The three files are only available inelectronic form at the Centre de Donnees Stellaires in Strasbourg, viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5), or viahttp://cdsweb.u-strasbg.fr/Abstract.html 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. Statistical Analysis of a Sample of Spectroscopic Binaries Containing Late Type GiantsAbstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993A&A...271..125B&db_key=AST Interferometric observations of double stars in 1986-1990A tabulation is presented for the measurements of double stars that havebeen conducted with the photometric phase-grating interferometer of theMt. Sanglok 1-m reflector. The tabulation encompasses the observationepoch, the position angle, the separation in arcsec, the magnitudedifference, formal errors in P.A. and separation, SAO number, andcoordinates for 2000.0. High-resolution spectroscopic survey of 671 GK giants. I - Stellar atmosphere parameters and abundancesA high-resolution spectroscopic survey of 671 G and K field giants isdescribed. Broad-band Johnson colors have been calibrated againstrecent, accurate effective temperature, T(eff), measurements for starsin the range 3900-6000 K. A table of polynomial coefficients for 10color-T(eff) relations is presented. Stellar atmosphere parameters,including T(eff), log g, Fe/H, and microturbulent velocity, are computedfor each star, using the high-resolution spectra and various publishedphotometric catalogs. For each star, elemental abundances for a varietyof species have been computed using a LTE spectrum synthesis program andthe adopted atmosphere parameters. Spectroscopic binaries - 15th complementary catalogPublished observational data on the orbital characteristics of 436spectroscopic binaries, covering the period 1982-1986, are compiled intables. The data sources and the organization of the catalog are brieflydiscussed, and notes are provided for each item. Interferometric Observations of Double Stars in 1985 and 1986Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1988A&AS...72..563T&db_key=AST E. W. Fick Observatory stellar radial velocity measurements. I - 1976-1984Stellar radial velocity observations made with the large vacuumhigh-dispersion photoelectric radial velocity spectrometer at FickObservatory are reported. This includes nearly 2000 late-type starsobserved during 585 nights. Gradual modifications to this instrumentover its first eight years of operation have reduced the observationalerror for high-quality dip observations to + or - 0.8 km/s. Visual multiples. VIII - 1000 MK typesA total of 1000 new classifications are given for stars brighter than B= 8.0 mag in the Aitken double star catalog. The classificationssupplement 865 classifications obtained in 1981 and 1984. Among thenewly discovered stars are 12 new Ap stars, eight Lambda Bootis stars,one Ba II star, and 60 Am stars. A detailed list of the newclassifications is given. Binary stars unresolved by speckle interferometry. IIIThe KPNO's 4-m telescope was used in 1975-1981 to determine the epochsof 1164 speckle observations for 469 unresolved, known or suspectedbinary stars. The data, presented in tabular form, encompass visualbinaries with eccentric orbits, occultation binaries, astrometricbinaries, Hyades stars of known or suspected duplicity, and many longperiod spectroscopic binaries. Radial-velocity orbits of HR 5553 and HR 6524Determinations are made of the orbital elements for the two single-linespectroscopic binaries HR 5553 and HR 6524. The former is found to havea period of 125.369 days and an eccentricity of 0.51 and the latter aperiod of 416.1 days and an eccentricity of 0.21. Since there is noevidence of a second star dip in the radial-velocity scans, it isassumed that the second star is fainter in each case. This is seen asimplying an upper limit for the mass of the second star which in turnimplies a lower limit for the inclination angle (i) for these systems.It is considered extremely unlikely that either of these binaries wouldproduce observable eclipses for any reasonable assumed values of theradii of the secondary stars. Duplicity in the solar neighborhood. II - Spectroscopic orbits for four bright stars HD 21018, HD 30021, HD 158837, and HD 190658Orbital elements have been determined for four stars from the brightstar catalog; HD 21018, HD 30021, HD 158837, and HD 190658. The rotationof these stars has been determined, and HD 21018 is shown to be a giantin rapid non-synchronous rotation. HD 190658 is an M2III giant whichcould fill its Roche lobe and eventually show eclipses. HD 190658 isalso a high velocity star (-112.1 km/s) and has the peculiarity ofhaving the shortest period (198 days) of any binary of type M III. Itshould also be noted that these stars are all members of triple systems. Binary Stars Unresolved by Speckle Interferometry - Part TwoAbstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1981PASP...93..221M&db_key=AST Binary stars unresolved by speckle interferometryThe epochs of 372 speckle observations obtained with the 4-m Mayalltelescope at KPNO during 1975-77 are given for 156 unresolved visual,astrometric, spectrum, occultation, and spectroscopic binary stars.Specified thresholds are set for detectible angular separations andmagnitude differences so that the negative observations presented herecan be used to place constraints on orbital parameters. MK classifications for F-and G-type stars. 3.Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974AJ.....79..682H&db_key=AST Micrometer Measures of Double Stars.Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1961ApJS....6....1K&db_key=AST Micrometer Measures of Double Stars.Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1959ApJS....4...45V&db_key=AST Micrometer measures of double stars.Not Available Magnitudes and colors for 833 Northern and Southern stars.Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1955AJ.....60...65E&db_key=AST Double star observations at Lick ObservatoryAbstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1954AJ.....59..388M&db_key=AST Mesures d'Etoiles Doubles effectuées à l'Observatoire du Pic-du-Midi en juillet-août 1951Not Available
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