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Reduction of CCD observations of visual binaries using the ``Tepui'' function as PSF
429 CCD measurements of relative positions and magnitude differences inV and R photometric bands for 165 visual double and multiple stars aregiven. CCD frames were taken at the 1.52 m Spanish telescope of theSpanish-German Center of Astronomy at Calar Alto (Almería,Spain). During the reduction process a ``Tepui" function was used as thePSF function.Tables 1 and 2 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/416/811

Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 Parsecs: The Northern Sample. I.
We have embarked on a project, under the aegis of the Nearby Stars(NStars)/Space Interferometry Mission Preparatory Science Program, toobtain spectra, spectral types, and, where feasible, basic physicalparameters for the 3600 dwarf and giant stars earlier than M0 within 40pc of the Sun. In this paper, we report on the results of this projectfor the first 664 stars in the northern hemisphere. These resultsinclude precise, homogeneous spectral types, basic physical parameters(including the effective temperature, surface gravity, and overallmetallicity [M/H]), and measures of the chromospheric activity of ourprogram stars. Observed and derived data presented in this paper arealso available on the project's Web site.

Speckle Interferometry at the US Naval Observatory. VIII.
The results of 2044 speckle interferometric observations of doublestars, made with the 26 inch (66 cm) refractor of the US NavalObservatory, are presented. Each speckle interferometric observation ofa system represents a combination of over a thousand short-exposureimages. These observations are averaged into 1399 mean positions andrange in separation from 0.16" to 14.97", with a mean separation of2.51". This is the eighth in a series of papers presenting measuresobtained with this system and covers the period 2001 March 18 through2001 December 30.

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

Multicolour observations of nearby visual double stars. New CCD measurements and orbits
We present multicolour CCD observations of nine nearby visual doublestars obtained in August and September 1999 with the 1.3-m telescope atSkinakas Observatory. The results consist of relative positions (epochs,angular separations and position angles) and differential BV RIphotometry. We confirm the physical association in eight cases.Previously known orbits do not match the new data for three systems.Orbits have been recalculated when sufficient data were available. Weprincipally improve the precision of the known orbits for three binariesand show the acute lack of precision in two other cases. In one case,the components are shown to move apart with a linear relative speed of0.050\arcsec/yr. Skinakas Observatory is a collaborate project of theUniversity of Crete, the Foundation for Research and Technology -Hellas, and the Max-Planck-Institut für Extraterrestrische Physik.

Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521

Speckle Interferometry at the US Naval Observatory. VI.
The results of 1068 speckle interferometric observations of doublestars, made with the 26 inch (0.66 m) refractor of the US NavalObservatory, are presented. These observations are averaged into 841means of 815 binary stars. The systems range in separation from 0.22" to6.01" with a mean separation of 2.21" and have a limiting secondarymagnitude of V=12.5. This is the sixth in a series of papers presentingmeasures obtained with this system, and it covers the period 1999January 1 through 2000 January 9.

Micrometer measurements of double stars made at the Côte D'Azur and Calar Alto observatories
We report 312 micrometer measurements of 155 visual double stars madewith the 50 cm refractor at the Côte D'Azur observatory (Nice,France) and with the 152 cm telescope at Calar Alto observatory(Almería, Spain).

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.

CCD measurements of visual double stars from the German-Spanish Astronomical Center at Calar Alto
342 CCD measurements of relative positions and magnitude differences for145 visual double stars are presented. Observations were carried out atthe 1.23m telescope of the German-Spanish Astronomical Center at CalarAlto (Spain), all of them in V and R photometric bands.

Photometric Measurements of the Fields of More than 700 Nearby Stars
In preparation for optical/IR interferometric searches for substellarcompanions of nearby stars, we undertook to characterize the fields ofall nearby stars visible from the Northern Hemisphere to determinesuitable companions for interferometric phase referencing. Because theKeck Interferometer in particular will be able to phase-reference oncompanions within the isoplanatic patch (30") to about 17th magnitude atK, we took images at V, r, and i that were deep enough to determine iffield stars were present to this magnitude around nearby stars using aspot-coated CCD. We report on 733 fields containing 10,629 measurementsin up to three filters (Gunn i, r and Johnson V) of nearby stars down toabout 13th magnitude at V.

Speckle Interferometry at the US Naval Observatory. IV.
The results of 1314 speckle interferometric observations of 625 binarystars, ranging in separation from 0.2" to 5.2" with a limiting secondarymagnitude of V=11, are tabulated. These observations were obtained usingthe 66 cm refractor at the US Naval Observatory in Washington, DC, withan intensified CCD detector. This is the fourth in a series of paperspresenting measures obtained with this equipment and covers the period1997 January 1 through December 31. Random errors for all measures areestimated to be 18 mas in separation and 0.57d/rho in position angle,where rho is the separation in arcseconds.

Speckle Interferometry at the US Naval Observatory. III.
Position angles and separations resulting from 2578 speckleinterferometric observations of 590 binary stars are tabulated. This isthe third in a series of papers presenting measures obtained using the66 cm refractor at the US Naval Observatory in Washington, DC, andcovers the period from 1995 June through 1996 December. Program starsrange in separation from 0.2" to 4.3", with a limiting magnitude ofV=11. Random errors are estimated to be 17.0 mas in separation and0.56d/rho in position angle, where rho is the separation in arcseconds.These are the first results acquired using an improved intensified CCDdetector. The new detector, in concert with an intensity-filteringtechnique applied in software, has permitted a 1 mag increase in dynamicrange, to 3.5 mag, for pairs separated by about 2". The instrumentationand calibration are briefly described, with an emphasis on thecharacteristics of the new detector. The software filter used toincrease the dynamic range is also described.

Speckle Interferometry at the US Naval Observatory. II.
Position angles and separations resulting from 2406 speckleinterferometric observations of 547 binary stars are tabulated. This isthe second in a series of papers presenting measures obtained using the66 cm refractor at the US Naval Observatory in Washington, DC, with anintensified CCD detector. Program stars range in separation from 0.2" to3.8", with Deltam<=2.5 mag and a limiting magnitude of V=10.0. Theobservation epochs run from 1993 January through 1995 August. Randomerrors are estimated to be 14 mas in separation and 0.52d/rho inposition angle, where rho is the separation in arcseconds. Theinstrumentation and calibration are briefly described. Aspects of thedata analysis related to the avoidance of systematic errors are alsodiscussed.

Visual binary orbits and masses POST HIPPARCOS
The parallaxes from Hipparcos are an important ingredient to derive moreaccurate masses for known orbital binaries, but in order to exploit theparallaxes fully, the orbital elements have to be known to similarprecision. The present work gives improved orbital elements for some 205systems by combining the Hipparcos astrometry with existing ground-basedobservations. The new solutions avoid the linearity constraints andomissions in the Hipparcos Catalog by using the intermediate TransitData which can be combined with ground-based observations in arbitarilycomplex orbital models. The new orbital elements and parallaxes give newmass-sum values together with realistic total error-estimates. To getindividual masses at least for main-sequence systems, the mass-ratioshave been generally estimated from theoretical isochrones and observedmagnitude-differences. For some 25 short-period systems, however, trueastrometric mass-ratios have been determined through the observedorbital curvature in the 3-year Hipparcos observation interval. Thefinal result is an observed `mass-luminosity relation' which falls closeto theoretical expectation, but with `outliers' due to undetectedmultiplicity or to composition- and age-effects in the nonuniformnear-star sample. Based in part on observations collected with the ESAHipparcos astrometry satellite. Tables~ 1, 3, 4 and 6 are also availablein electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr~(130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html

Micrometer measurements of double stars from the Spanish observatories at Calar Alto and Santiago de Compostela.
This paper reports 458 micrometer observations of visual double starsmade with the 152 cm. telescope at Calar Alto Observatory (Almeria,Spain) and with the 35 cm. telescope at Ramon Maria Aller Observatory(Santiago de Compostela, Spain). Tables 1 and 2 only available inelectronic form at CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html

Micrometer measurements of visual double stars made at the Cote d'Azur Observatory.
Not Available

ICCD Speckle Observations of Binary Stars. XVII. Measurements During 1993-1995 From the Mount Wilson 2.5-M Telescope.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....114.1639H&db_key=AST

Speckle Interferometry at the US Naval Observatory. I.
We present speckle interferometer measurements of 467 binary stars takenat the US Naval Observatory in Washington, DC, using the 66 cmrefractor, from 1990 October through 1992 December. The observingprogram is designed to provide high-quality observations of binaries inthe 0."3--3."5 range of separations and as faint as 10.0 mag. More than8000 measurements have been made to date, of which we report the resultsfor 2329. Not only is it our intent to provide accurate data forinteresting binary stars, but also, by careful calibration, to firmlyrelate the "classical" astrometry of binary stars to that being obtainedtoday by speckle and that which will soon be obtained by other moderntechniques such as long-baseline optical interferometry.

Photovisual Magnitude Differences for 169 Double Stars
Photovisual magnitude differences determined from multi-exposurephotographic plates for 169 double stars are presented. The separationsrange from 1.5'' to 113\arcsec, and the photovisual magnitudedifferences vary from 0.03 to 6.14 magnitudes. The internal mean errorof a single magnitude difference estimate is +/-0.064 magnitude.

ICCD Speckle Observations of Binary Stars. XII. Measurements During 1984-1986 From the Perkins 1.8 M Telescope
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996AJ....111..393A&db_key=AST

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.

Micrometer measurements of visual double stars made at the Spanish observatories at Calar Alto and Fabra
The study presents 184-micrometer measurements of 100 double starsobserved with the 152-cm telescope at Calar Alto (Almeria, Spain) andthe 38-cm refractor at Fabra Observatory (Barcelona, Spain). The epoch,observed position angle, angular distance between components, number ofnights on which the star was observed, and an indication of the observerare given. Orbits were calculated for almost all the observed stars.

Radial velocity measurements of visual binary stars
Observations on a correlation radial spectrometer of 31 visual binarysystems with components of late-type spectral classes are reported. Theobservations were made in order to resolve the 180-deg ambiguity of thelongitude of the ascending node. For 11 systems with angular separationsgreater than 1.5 arcsec, the components' velocities were measuredseparately. For 12 systems with angular separations in the range 0.2-1.5arcsec, the sign of radial velocity was obtained with the differentialobservation method. Additional spectroscopic components were detected inthree systems. On the basis of the observations, the true ascending nodeof the orbit was determined for 16 systems. The velocities of the otherfive systems were measured without resolution into components.

A radio optical reference frame. III - Additional radio and optical positions in the Southern Hemisphere
Radio and optical positions are presented for southern hemisphereextragalactic sources from the Parkes 2.7 GHz survey. Sixty-one sourceswere observed with Mark III VLBI at 8.4 GHz between Tidbinbilla,Australia, and Hartebeesthoek, South Africa. The results presented arepart of the effort to establish a global reference frame of 400extragalactic radio sources. Radio positions with about 10 milliarcsecerrors have been estimated for 39 sources not previously in the presentradio reference frame catalog, and provisional positions were obtainedfor two additional sources, bringing the total number of catalog sourcesto 276. The principal source of error is the uncalibrated ionosphere. Ofthe remaining sources five were completely undetected, six were eithertoo faint or too resolved, and nine had previous catalog positions.Optical positions on the FK5 system have also been measured for foursouthern sources using prime focus plates from the Anglo-Australian 4 mtelescope with an accuracy of 0.06 arcsec. This raises to 40 the numberof radio sources with accurately measured positions for their opticalcounterparts.

Micrometer measurements of visual double stars made at Nice
Three-hundred thirty-five micrometer measurements of visual double starsmade at Nice Observatory with the 50-cm and 74-cm refractors arereported. The tables give the Washington Catalog number, letters of thecomponents if the star is multiple, the Aitken Catalog number, theobservational epoch, the observed position angle and angular distance,the number of nights, and the name of the observer.

Multiplicity among solar-type stars in the solar neighbourhood. II - Distribution of the orbital elements in an unbiased sample
An unbiased sample of 164 primary G-dwarf stars in the solarneighborhood are studied with the aid of 4200 radial velocities obtainedduring almost 13 yrs. Several present-day distributions of the orbitalelements are derived. For systems with M(2)/M(1) above 0.1 in the nearbyG-dwarf sample, the following results are obtained: (1) The orbitalperiod distribution is unimodal and can be approximated by aGaussian-type relation with a median period of 180 yrs. (2) The shortbinaries are circularized up to orbital periods of about 11 d due to thetidal evolution effects - a result compatible with the mean age of theGalactic disk. (3) The tight binaries not affected by tidal effects (inthe range between 11 and 1000 d) may reflect the initial binaryformation process, and they have a mean eccentricity of 0.31 +/-0.04.For systems with M(2)/M(1) not greater than 0.1, the proportion of browndwarf companions among the IAU velocity standards is estimated at 10percent of the primaries, a value in good agreement with that found inthe G-dwarf sample.

Multiplicity among solar type stars in the solar neighbourhood. I - CORAVEL radial velocity observations of 291 stars
Results obtained on stellar radial velocity of 291 stars of spectraltypes FO to G9, measured with CORAVEL spectrometers at theHaute-Provence and la Silla Observatories, are discussed. The paperdescribes the observational procedure, reduction technique, andvelocity-data calibration and presents a list of individualradial-velocity measurements. Few histograms describing the survey arealso presented.

Catalogue of Variable or Suspected Stars Nearby the Sun
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1990A&AS...85..971P&db_key=AST

Micrometer observations of double stars from the Fabra Observatory
The 38-cm refractor at the Fabra Observatory in Spain was used to obtain150 micrometer observations of 61 double stars. In tabular form, eachstar is listed by its WDS number, the letters of its components (ifmultiple), its ADS number, the observation epoch, the observed positionsangle, and the angular distance between the components. For the multipleobservations, in no case did the averaged measurements differ by morethan 3 deg for positions or 0.10 arcsec for angular separations.

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Datos observacionales y astrométricos

Constelación:Cisne
Ascensión Recta:19h45m33.55s
Declinación:+33°36'06.1"
Magnitud Aparente:8.367
Distancia:20.371 parsecs
Movimiento Propio en Ascensión Recta:18.9
Movimiento Propio en Declinación:-445.8
B-T magnitude:9.668
V-T magnitude:8.475

Catálogos y designaciones:
Nombres Propios   (Edit)
HD 1989HD 186858
TYCHO-2 2000TYC 2660-31-1
USNO-A2.0USNO-A2 1200-13071967
HIPHIP 97222

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