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MK Classification and Dynamical Masses for Late-Type Visual Binaries
On the basis of slit spectra obtained with the SCORPIO spectral cameraattached to the 2.6 m telescope of the V. Ambartsumian ByurakanAstrophysical Observatory (Armenia), MK classifications for 30 visualbinaries comprising mostly late K and M type stars are presented.Comparison with other determinations shows that this configurationprovides a reliable MK classification. Dynamical masses for 25 systemsare computed. Using standard mass-luminosity calibrations, individualmass sums for 11 pairs consisting of virtually single, nonvariabledwarfs are calculated, showing a good agreement with correspondingdynamical masses. The dynamical parallax of HIP 112354 is closer to thetrigonometric parallax given in the Yale General Catalogue ofTrigonometric Stellar Parallaxes (van Altena et al.) than to theHipparcos parallax.
| Speckle Measurements and Differential Photometry of Visual Binaries with the 6 Meter Telescope of the Special Astrophysical Observatory
Results of speckle measurements and differential photometry carried outwith the 6 m telescope of the Special Astrophysical Observatory (Russia)at the end of 2004 are presented. One new (COU 1569) and four improvedorbits (ADS 440AC, ADS 1729, ADS 5726, and COU 1897), as well as theirdynamical mass estimates, are reported.
| High-Resolution Spectroscopy of Ursa Major Moving Group Stars
We use new and extant literature spectroscopy to address abundances andmembership for UMa moving group stars. We first compare the UMa, Coma,and Hyades H-R diagrams via a homogeneous set of isochrones and findthat these three aggregates are essentially coeval; this (near)coevality can explain the indistinguishable distributions of UMa andHyades dwarfs in the chromospheric emission versus color plane. Ourspectroscopy of cool UMa dwarfs reveals striking abundanceanomalies-trends with Teff, ionization state, and excitationpotential-like those recently seen in young, cool M34, Pleaides, andHyades dwarfs. In particular, the trend of rising λ7774-based O Iabundance with declining Teff is markedly subdued in UMacompared to the Pleiades, suggesting a dependence on age or metallicity.Recent photometric metallicity estimates for several UMa dwarfs aremarkedly low compared to the group's canonical metallicity, and similardeviants are seen among cool Hyads as well. Our spectroscopy does notconfirm these curious photometric estimates, which seem to be calledinto question for cool dwarfs. Despite disparate sources of Li data, ourhomogeneous analysis indicates that UMa members evince remarkably smallscatter in the Li-Teff plane for Teff>=5200 K.Significant star-to-star scatter suggested by previous studies is seenfor cooler stars. Comparison with the consistently determined HyadesLi-Teff trend reveals differences that are qualitativelyconsistent with this cluster's larger [Fe/H] (and perhaps slightlygreater age). However, quantitative comparison with standard stellarmodels indicates the differences are smaller than expected, suggestingthe action of a fourth parameter beyond age, mass, and [Fe/H]controlling Li depletion. The UMa-Coma cool star Li abundances may showa slight 0.2 dex difference; however, this may be mass-independent andthus more consistent with a modest initial Li abundance difference.This paper includes data taken at the McDonald Observatory of theUniversity of Texas at Austin.Based on observations obtained at Kitt Peak National Observatory, adivision of the National Optical Astronomy Observatories, which isoperated by the Association of Universities for Research in Astronomy,Inc., under cooperative agreement with the National Science Foundation.
| Speckle Observations of Binary Stars with the WIYN Telescope. IV. Differential Photometry
Five hundred seventy-six magnitude difference measures are presented for260 binary stars. These measures are derived from CCD-based speckleobservations taken at the WIYN 3.5 m telescope at Kitt Peak NationalObservatory during the period 1997-2000. Separations of the systemsrange from over 1" down to near the diffraction limit of the telescope.A study of multiple measures of the same targets indicates that themeasures have a typical uncertainty of better than 0.13 mag per 2 minuteobservation, and that multiple observations can be averaged to arrive atsmaller uncertainties. Results presented here are also compared, insofaras it is possible, with measures in the Hipparcos Catalogue and toprevious studies using adaptive optics. No major systematic errors wereidentified.The WIYN Observatory is a joint facility of the University ofWisconsin-Madison, Indiana University, Yale University, and the NationalOptical Astronomy Observatory.
| Stellar Kinematic Groups. II. A Reexamination of the Membership, Activity, and Age of the Ursa Major Group
Utilizing Hipparcos parallaxes, original radial velocities and recentliterature values, new Ca II H and K emission measurements,literature-based abundance estimates, and updated photometry (includingrecent resolved measurements of close doubles), we revisit the UrsaMajor moving group membership status of some 220 stars to produce afinal clean list of nearly 60 assured members, based on kinematic andphotometric criteria. Scatter in the velocity dispersions and H-Rdiagram is correlated with trial activity-based membership assignments,indicating the usefulness of criteria based on photometric andchromospheric emission to examine membership. Closer inspection,however, shows that activity is considerably more robust at excludingmembership, failing to do so only for <=15% of objects, perhapsconsiderably less. Our UMa members demonstrate nonzero vertex deviationin the Bottlinger diagram, behavior seen in older and recent studies ofnearby young disk stars and perhaps related to Galactic spiralstructure. Comparison of isochrones and our final UMa group membersindicates an age of 500+/-100 Myr, some 200 Myr older than thecanonically quoted UMa age. Our UMa kinematic/photometric members' meanchromospheric emission levels, rotational velocities, and scattertherein are indistinguishable from values in the Hyades and smaller thanthose evinced by members of the younger Pleiades and M34 clusters,suggesting these characteristics decline rapidly with age over 200-500Myr. None of our UMa members demonstrate inordinately low absolutevalues of chromospheric emission, but several may show residual fluxes afactor of >=2 below a Hyades-defined lower envelope. If one defines aMaunder-like minimum in a relative sense, then the UMa results maysuggest that solar-type stars spend 10% of their entire main-sequencelives in periods of precipitously low activity, which is consistent withestimates from older field stars. As related asides, we note six evolvedstars (among our UMa nonmembers) with distinctive kinematics that liealong a 2 Gyr isochrone and appear to be late-type counterparts to diskF stars defining intermediate-age star streams in previous studies,identify a small number of potentially very young but isolated fieldstars, note that active stars (whether UMa members or not) in our samplelie very close to the solar composition zero-age main sequence, unlikeHipparcos-based positions in the H-R diagram of Pleiades dwarfs, andargue that some extant transformations of activity indices are notadequate for cool dwarfs, for which Ca II infrared triplet emissionseems to be a better proxy than Hα-based values for Ca II H and Kindices.
| 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.
| 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.
| Speckle Observations of Binary Stars with the WIYN Telescope. II. Relative Astrometry Measures during 1998-2000
Five hundred twelve relative astrometry measures are presented for 253double stars, including 53 double stars discovered by Hipparcos. In 15cases, relative astrometry is reported for the first time for newlyconfirmed pairs. In addition, 20 high-quality nondetections ofcompanions are reported for stars suspected of being nonsingle byHipparcos. Observations were taken using a fast-readout CCD camerasystem at the WIYN 3.5 m telescope at Kitt Peak, Arizona. In comparingthese measures with ephemeris predictions for binary stars with verywell known orbits, we find that the measurement precision is better than3 mas in separation and 1° in position angle per individualobservation. Measurement precision and detection capabilities are fullydiscussed, and confirmed orbital motion is reported in four cases of theHipparcos double star discoveries. The WIYN Observatory is a jointfacility of the University of Wisconsin-Madison, Indiana University,Yale University, and the National Optical Astronomy Observatory.
| 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
| Astrometric radial velocities. III. Hipparcos measurements of nearby star clusters and associations
Radial motions of stars in nearby moving clusters are determined fromaccurate proper motions and trigonometric parallaxes, without any use ofspectroscopy. Assuming that cluster members share the same velocityvector (apart from a random dispersion), we apply a maximum-likelihoodmethod on astrometric data from Hipparcos to compute radial and spacevelocities (and their dispersions) in the Ursa Major, Hyades, ComaBerenices, Pleiades, and Praesepe clusters, and for theScorpius-Centaurus, alpha Persei, and ``HIP 98321'' associations. Theradial motion of the Hyades cluster is determined to within 0.4 kms-1 (standard error), and that of its individual stars towithin 0.6 km s-1. For other clusters, Hipparcos data yieldastrometric radial velocities with typical accuracies of a few kms-1. A comparison of these astrometric values withspectroscopic radial velocities in the literature shows a good generalagreement and, in the case of the best-determined Hyades cluster, alsopermits searches for subtle astrophysical differences, such as evidencefor enhanced convective blueshifts of F-dwarf spectra, and decreasedgravitational redshifts in giants. Similar comparisons for the ScorpiusOB2 complex indicate some expansion of its associations, albeit slowerthan expected from their ages. As a by-product from the radial-velocitysolutions, kinematically improved parallaxes for individual stars areobtained, enabling Hertzsprung-Russell diagrams with unprecedentedaccuracy in luminosity. For the Hyades (parallax accuracy 0.3 mas), itsmain sequence resembles a thin line, possibly with wiggles in it.Although this main sequence has underpopulated regions at certaincolours (previously suggested to be ``Böhm-Vitense gaps''), suchare not visible for other clusters, and are probably spurious. Futurespace astrometry missions carry a great potential for absoluteradial-velocity determinations, insensitive to the complexities ofstellar spectra. Based on observations by the ESA Hipparcos satellite.Extended versions of Tables \ref{tab1} and \ref{tab2} are available inelectronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.125.8) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/381/446
| Late-type members of young stellar kinematic groups - I. Single stars
This is the first paper of a series aimed at studying the properties oflate-type members of young stellar kinematic groups. We concentrate ourstudy on classical young moving groups such as the Local Association(Pleiades moving group, 20-150Myr), IC 2391 supercluster (35Myr), UrsaMajor group (Sirius supercluster, 300Myr), and Hyades supercluster(600Myr), as well as on recently identified groups such as the Castormoving group (200Myr). In this paper we compile a preliminary list ofsingle late-type possible members of some of these young stellarkinematic groups. Stars are selected from previously established membersof stellar kinematic groups based on photometric and kinematicproperties as well as from candidates based on other criteria such astheir level of chromospheric activity, rotation rate and lithiumabundance. Precise measurements of proper motions and parallaxes takenfrom the Hipparcos Catalogue, as well as from the Tycho-2 Catalogue, andpublished radial velocity measurements are used to calculate theGalactic space motions (U, V, W) and to apply Eggen's kinematic criteriain order to determine the membership of the selected stars to thedifferent groups. Additional criteria using age-dating methods forlate-type stars will be applied in forthcoming papers of this series. Afurther study of the list of stars compiled here could lead to a betterunderstanding of the chromospheric activity and their age evolution, aswell as of the star formation history in the solar neighbourhood. Inaddition, these stars are also potential search targets for directimaging detection of substellar companions.
| Dusty Debris around Solar-Type Stars: Temporal Disk Evolution
Using ISO-ISOPHOT, we carried out a survey of almost 150 stars to searchfor evidence of emission from dust orbiting young main-sequence stars,both in clusters and isolated systems. Over half of the detections arenew examples of dusty stellar systems and demonstrate that such dust canbe detected around numerous stars older than a few times 106yr. Fluxes at 60 and either 90 or 100 μm for the new excess sourcestogether with improved fluxes for a number of IRAS-identified sourcesare presented. Analysis of the excess luminosity relative to the stellarphotosphere shows a systematic decline of this excess with stellar ageconsistent with a power-law index of -2.
| 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 Observations of Double Stars with PISCO at Pic du Midi: Measurements in 1998
We present astrometric measurements of binary stars based on speckleobservations of 164 independent sequences of observations(~104 frames each) made with the PISCO speckle camera at Picdu Midi. These measurements concern 147 objects, of which 134 were foundto be double with a separation in the range 0.1"-1.0". These objectswere mainly selected among grade 3 orbits to improve the accuracy oftheir orbits and to constrain their masses. We discovered the binarityof 59 Aql with an angular separation of 0.09"+/-0.01".
| 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.
| 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.
| 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.
| 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
| 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.
| Photographic astrometry of binar and proper-motion stars: 8.
300 trigonometric parallaxes, 15 revised binary-star orbits, and 24 massratios are listed and annotated.
| Binary star speckle measurements during 1989-1993 from the SAO 6 M and 1 M telescopes in Zelenchuk
We have continued to survey visual and interferometric binary stars withsignificant orbital motion by means of speckle method at the telescopesof the Special Astrophysical Observatory (SAO) in Zelenchuk. Here wepresent the lists of 267 speckle observations made with the 6 m and the1 m telescopes in the period May 1989-November 1993.
| Rotation and activity among solar-type stars of the Ursa Major Group
We examine rotation and chromospheric activity among G and K dwarfsrecently shown to be members of the Ursa Major Group (UMaG). Rotationperiods for UMaG stars are smaller than for stars of the same colors inthe Hyades, and by an amount corresponding to the Skumanich relation.Most UMaG stars have about the same level of Ca II and K emission,implying that they also have nearly uniform intrinsic rotation rates.That means that the diversity of rotation rates and levels of activityseen among solar-type stars in the Alpha Persei and Pleiades clustershas largely converged by the age of UMaG (0.3 Gyr).
| The evolution of the lithium abundances of solar-type stars. II - The Ursa Major Group
We draw upon a recent study of the membership of the Ursa Major Group(UMaG) to examine lithium among 0.3 Gyr old solar-type stars. For most Gand K dwarfs, Li confirms the conclusions about membership in UMaGreached on the basis of kinematics and chromospheric activity. G and Kdwarfs in UMaG have less Li than comparable stars in the Pleiades. Thisindicates that G and K dwarfs undergo Li depletion while they are on themain sequence, in addition to any pre-main-sequence depletion they mayhave experienced. Moreover, the Li abundances of the Pleiades K dwarfscannot be attributed to main-sequence depletion alone, demonstratingthat pre-main-sequence depletion of Li also takes place. The sun's Liabundance implies that the main-sequence mechanism becomes lesseffective with age. The hottest stars in UMaG have Li abundances likethose of hot stars in the Pleiades and Hyades and in T Tauris, and thetwo genuine UMaG members with temperatures near Boesgaard's Li chasmhave Li abundances consistent with that chasm developing fully by 0.3Gyr for stars with UMaG's metallicity. We see differences in theabundance of Li between UMaG members of the same spectral types,indicating that a real spread in the lithium abundance exists withinthis group.
| Stellar kinematic groups. I - The Ursa Major group
The Ursa Major Group (UMaG) is studied as a test case for theauthenticity of Stellar Kinematic Groups, using Coravel radialvelocities, recent compilations of astrometric data, and newspectroscopic observations. Spectroscopic age indicators, particularlyindices of the strength of chromospheric emission, are applied tosolar-type candidate members of UMaG, and it is shown that stars thatmeet the spectroscopic criteria also have kinematics that agree betterwith the space motions of the nucleus of UMaG than does the startingsample as a whole. The primary limitation on the precision of kinematicsis now parallaxes instead of radial velocities. These more restrictivekinematic criteria are then applied to other UMaG candidates and a listsummarizing membership is presented. UMaG is also examined as a cluster,confirming its traditional age of 0.3 Gyr, and a mean Fe/H of -0.08 +/-0.09 for those stars most likely to be bona fide members.
| 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.
| Observations of double stars and new pairs. XV
The study reports visual and photographic measures listed for 1150 pairsobtained in the time frame 1989.91-1992.15, including 221 new doublestars. Magnitudes were estimated for a part of the objects, especiallythe fainter ones. Plate orientations were calculated from field stars ofknown positions and were precessed to the epoch; numbers of nights andof measured exposures are given. Reobservation of faint, neglected pairsreveal many corrections to the data from the old discovery lists.
| 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.
| A study of excess H-alpha emission in chromospherically active M dwarf
Spectroscopic observations from three observatories are combined tostudy the properties of the excess H-alpha emission which characterizesthe most chromospherically active subset of the M dwarf stars, known asthe dMe stars. It is demonstrated that the excess H-alpha luminosityfrom these stars is a monotonically decreasing function of their (R-I)color, and evidence is presented which suggests that the product of themean surface brightness and the mean filling factor of the emissiveregions is essentially constant with color. Another significant resultof the study is a linear correlation between the excess luminosity inH-alpha and the coronal X-ray luminosity.
| Measurements of binaries made with the 152-cm telescope at Calar Alto
A total of 143 micrometer measurements are presented for 58 double starsobserved with the 152-cm telescope of the National AstronomicalObservatory at Calar Alto. This is the first published list ofobservations of this kind made with this telescope.
| Space motions of low-mass stars.
Radial-velocity measures are presented for 225 stars, most of which aredwarf K and M stars. The data were obtained with the CfA digitalspeedometer, whose uncertainty is less than 1 km/s. Calibrations ofthree earlier radial-velocity studies and comparisons with three othercontemporary ones lead to the evaluation of the standard error for anindividual star as determined in each investigation. The data from twomasks, matching solar type and M type stars, form a ratio that measuresstellar surface temperature quite closely and appear to be useful indetecting the presence of unseen companions. A few previouslyunrecognized binaries have been detected; those with most certaintyinclude stars nos. 366B, 453, and 46A of the McCormick lists of dwarfstars.
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