Binary Star Speckle Measurements with the 1.52-m telescope at Calar Alto
We present binary star interferometric measurements carried out on 2001July and 2004 February with our ICCD speckle camera attached to the1.52-m telescope of the Observatorio Astronómico Nacional atCalar Alto (Almería, Spain). Data comprise 120 observations of 87systems with the measured angular separations ranging from 0''.102 to6''.076. They are used to improve the orbital elements for STT 170 andSTF 1670 AB.
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Spectral Classification of the Hot Components of a Large Sample of Stars with Composite Spectra, and Implication for the Absolute Magnitudes of the Cool Supergiant Components.
A sample of 135 stars with composite spectra has been observed in thenear-UV spectral region with the Aurélie spectrograph at theObservatoire de Haute-Provence. Using the spectral classifications ofthe cool components previously determined with near infrared spectra, weobtained reliable spectral types of the hot components of the samplesystems. The hot components were isolated by the subtraction methodusing MK standards as surrogates of the cool components. We also derivedthe visual magnitude differences between the components usingWillstrop's normalized stellar flux ratios. We propose a photometricmodel for each of these systems on the basis of our spectroscopic dataand the Hipparcos data. We bring to light a discrepancy for the Gsupergiant primaries between the visual absolute magnitudes deduced fromHipparcos parallaxes and those tabulated by Schmidt-Kaler for the GIbstars: we propose a scale of Mv-values for these stars incomposite systems. By way of statistics, about 75% of the hot componentsare dwarf or subgiant stars, and 25% should be giants. The distributionin spectral types is as follows: 41% of B-type components, 57% of typeA, and 2% of type F; 68% of the hot components have a spectral type inthe range B7 to A2. The distribution of the ΔMv-valuesshows a maximum near 0.75 mag.
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Speckle Observations of Composite Spectrum Stars with PISCO in 1993-1998
We present speckle interferometry observations of 47 composite spectrumstars obtained between 1993 and 1998 at the Pic du Midi Observatory withthe PISCO speckle camera. 76% of over 150 independent 10 minutesequences of observations led to a companion detection. Binary componentangular separations ranged from 0.05" to 1.2". We also obtained a seriesof 23 measurements of an additional nine close binaries. PISCOobservations confirm, for the first time since their discovery, theduplicity of HD 29104 (L4), HD 83808 (WGT 1Aa), HD 183912 Aa' (BON Ap),and HD 156729 (HR 6436). Discovered as double by Hipparcos, theparticularly difficult to resolve HD 156729 was observed despite thelarge magnitude difference, Δm=4.2, between its two components.Based on observations made with the Télescope Bernard Lyot at Picdu Midi Observatory, France.
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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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A catalog of rotational and radial velocities for evolved stars
Rotational 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
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Spectral classifications in the near infrared of stars with composite spectra. III. Study of a sample of 137 objects with the Aurelie spectrograph
We provide spectral classifications for a sample of 137 stars mentionedas having composite spectra. The classifications were carried out on 33Angstroms /mm spectra in the region 8370 - 8870 Angstroms. Of these 137objects, 115 correspond in the infrared to cool stars (G, K or M) ofluminosity classes III, II and I; for 22 stars, we find only hot spectraof types B, A, F or Am, so that they do not fulfil our definition ofcomposite spectra. We detect four new Am stars, and one Am star (HD70826) turns out to be a composite spectrum object. As in Paper II, thecool components of composite spectra show a strong concentration in thevicinity of G8III. Based upon observations carried out at Observatoirede Haute-Provence (OHP).
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Ultraviolet and Optical Studies of Binaries with Luminous Cool Primaries and Hot Companions. V. The Entire IUE Sample
We have obtained or retrieved IUE spectra for over 100 middle- andlate-type giant and supergiant stars whose spectra indicate the presenceof a hot component earlier than type F2. The hot companions areclassified accurately by temperature class from their far-UV spectra.The interstellar extinction of each system and the relative luminositiesof the components are derived from analysis of the UV and opticalfluxes, using a grid of UV intrinsic colors for hot dwarfs. We find thatthere is fair agreement in general between current UV spectralclassification and ground-based hot component types, in spite of thedifficulties of assigning the latter. There are a few cases in which thecool component optical classifications disagree considerably with thetemperature classes inferred from our analysis of UV and opticalphotometry. The extinction parameter agrees moderately well with otherdeterminations of B-V color excess. Many systems are worthy of furtherstudy especially to establish their spectroscopic orbits. Further workis planned to estimate luminosities of the cool components from the dataherein; in many cases, these luminosities' accuracies should becomparable to or exceed those of the Hipparcos parallaxes.
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Spectral classifications in the near infrared of stars with composite spectra. II. Study of a sample of 180 stars
A sample of 180 supposedly composite-spectrum stars has been studied onthe basis of spectra obtained in the near infrared (8370-8780 Angstroms)at a dispersion of 33 Anstroms/mm. The objective was to study the coolercomponents of the systems. Of our sample, 120 are true compositespectra, 35 are hot spectra of types B, F and 25 are Am stars. We find astrong concentration of the cooler components of the composite spectraaround G8III. In view of the difficulty of classifying compositespectra, because of the super position of an early type dwarf and a latetype giant or supergiant spectrum, we have made several tests to controlthe classification based upon the infrared region. Since all tests gavepositive results, we conclude that our classifications can be consideredas being both reliable and homogeneous. Table \ref{tab1} is alsoavailable electronically at the CDS via anonymous ftp 130.79.128.5 orhttp://cdsweb.u-strasbg.fr/Abstracts.html} Based upon observationscarried out at Observatoire de Haute-Provence (CNRS).
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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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ICCD speckle observations of binary stars. X - A further survey for duplicity among the bright stars
Speckle interferometric observations are reported for 1123 starsselected from the Yale Bright Star Catalogue (BSC) in a continuingeffort to detect new binaries among the bright stars. Thirty-twopreviously unresolved binaries have been detected, including companionsto Xi UMa and 15 S Mon. Measures of 107 previously resolved systems,many of which resulted from earlier speckle observations, are alsopresented. No evidence of duplicity within a specific (m, Delta-m, rho)window of detectability was found for 984 bright stars. Many of thesystems discovered earlier have shown significant orbital motions, andwe present preliminary orbital elements for six binaries. This efforthas resulted in the discovery of 75 new, bright binaries. We considersome aspects of the duplicity frequencies among the diverse spectral andluminosity classes represented in this sample. We anticipate that thecompletion of a speckle survey of the BSC would lead to the discovery ofat least 200 additional binary systems with angular separations mostlybelow 0.20 arcsec. Many of these will have periods of the order of onedecade and will be accessible to complementary radial velocity programsof enhanced precision.
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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.
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All-sky Stromgren photometry of speckle binary stars
All-sky Stromgren photometric observations were obtained for 303 specklebinaries. Most stars were in the range of V = 5-8. These data, whencombined with ratios of intensities from the CHARA speckle photometryprogram, will allow the determination of photometric indices for theindividual components of binary stars with separations as small as 0.05arcsec. These photometric indices will complement the stellar massesfrom the speckle interferometry observations to provide a much improvedmass-luminosity relationship.
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ICCD speckle observations of binary stars. V - Measurements during 1988-1989 from the Kitt Peak and the Cerro Tololo 4 M telescopes
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1990AJ.....99..965M&db_key=AST
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ICCD speckle observations of binary stars. IV - Measurements during 1986-1988 from the Kitt Peak 4 M telescope
One thousand five hundred and fifty measurements of 1006 binary starsystems observed mostly during 1986 through mid-1988 by means of speckleinterferometry with the KPNO 4-m telescope are presented. Twenty-onesystems are directly resolved for the first time, including newcomponents to the cool supergiant Alpha Her A and the Pleiades shellstar Pleione. A continuing survey of The Bright Star Catalogue yieldedeight new binaries from 293 bright stars observed. Corrections tospeckle measures from the GSU/CHARA ICCD speckle camera previouslypublished are presented and discussed.
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On the (B-V) colors of the bright stars
The possible causes of the dispersion of (B-V) colors of nearby stars inthe Bright Star Catalog are investigated. The distribution of (B-V)colors is presented for the entire range of spectral classes.Explanations for the dispersion in terms of a nonuniform distribution ofinterstellar absorbing material and a variability of metallicity areaddressed. A new statistical model for reddening by interstellar dustclouds is developed. It is concluded that extinction by nonuniforminterstellar matter is an important contribution to the reddening ofnearby stars, and that a part of the dispersion of (B-V) colors of Kand, possibly, M giants may be due to some unidentified variableproperty of those stars.
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ICCD speckle observations of binary stars. II - Measurements during 1982-1985 from the Kitt Peak 4 M telescope
This paper represents the continuation of a systematic program of binarystar speckle interferometry initiated at the 4 m telescope on Kitt Peakin late 1975. Between 1975 and 1981, the observations were obtained witha photographic speckle camera, the data from which were reduced byoptical analog methods. In mid-1982, a new speckle camera employing anintensified charge-coupled device as the detector continued the programand necessitated the development of new digital procedures for reducingand analyzing speckle data. The camera and the data-processingtechniques are described herein. This paper presents 2780 newmeasurements of 1012 binary and multiple star systems, including thefirst direct resolution of 64 systems, for the interval 1982 through1985.
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Narrow-band photometry of late-type stars. II
This paper presents extensive narrow-band photometry in the Uppsalasystem supplementing earlier published mesurements so that data now areavailable for all late-type stars brighter than V = 6.05 and a number ofgalactic cluster members. Numerous UBV and BV measurements are alsopublished. The data are used to determine relations for the predictionof UBV intrinsic colors for late-type stars from the narrow-bandmeasurements. The main purpose of the data is to constitute the basisfor the determination of solar-neighborhood space densities of late-typestars, mainly giants of different kinds; these space densities will becombined with narrow-band data for fainter stars in the north Galacticpole region to yield the decrease of space density with distance fromthe galactic plane for many kinds of late-type stars.
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Micrometer Measurements of Visual Double Stars - Part Three -
Not Available
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Orbits of 20 visual binaries
Orbital elements of 20 visual binaries have been determined fromobservations in 1984 and 1985. The pairs include 14 Lyn, Mu Vel, IotaLeo, and 77 Cyg. At least eight objects are evolved and two containsubsystems. The binaries are listed along with their elements andephemerides. The observations and residuals are also given. Comments oneach of the objects are presented.
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Speckle interferometric measurements of binary stars. VIII
Six hundred measurements of 331 binary stars observed during 1980 bymeans of speckle interferometry with the 4 m telescope at Kitt PeakNational Observatory are presented. Thirty-two systems are directlyresolved for the first time. Newly resolved spectroscopic binariesinclude HR 2001, 53 Dam, HR 6388, HR 6469, 31 Omicron-2 Cyg, HR 7922,and alpha Equ.
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Medium resolution spectra of G, K and M stars in the near infrared
This paper describes the medium-resolution spectra of a small sample ofG, K and M stars in the near infrared region, obtained with the Reticonsystem at Cima Ekar Observatory. The resolution of 6 A permits adiscussion of atomic and molecular features useful for spectraclassification while preserving at the same time the information contentof the continuum.
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Visual Double Stars for the Amateur
Not Available
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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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Visual multiples. V - Radial velocities of 160 systems
937 radial velocities are listed from coude spectra of 160 visualmultiples with known visual orbital elements; these, plus the velocitiesin paper of Roemer and Sanwal (1980), are discussed. Among the resultsare (1) systems yielding spectroscopic elements with the visual period,(2) systems probably showing velocity variations during the visualperiod, (3) systems with short spectroscopic periods, some in additionto detectable motion during the visual period, (4) systems showing novariation in radial velocity during the visual period, either becausethe components are similar in brightness or the periods are very long,(5) systems with spectral lines too broad to allow the detection oforbital motion, and (6) systems with insufficient data for anyconclusions to be drawn at present.
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Observations of binary stars by speckle interferometry. II
This is the second paper in a series describing observations of binarystars using the technique of speckle interferometry. Observations weremade using the 2.5-m Newton Telescope and the 1-m telescope of the RoyalGreenwich Observatory and the 1.9-m telescope of the South AfricanAstronomical Observatory. The classical Rayleigh diffraction limits are0.050 arcsec for the 2.5-m telescope, 0.065 arcsec for the 1.9-mtelescope and 0.125 arcsec for the 1-m telescope, at a wavelength of 500nm. The results of 29 measurements of 26 objects are presented. Theobjects include long period spectroscopic binaries from the 6th Catalogof Batten, close visual binary systems from the 3rd Catalog of Finsenand Worley and variable stars. Nine of the objects have not beenpreviously resolved by speckle interferometry. New members are detectedin the systems Beta Cep, p Vel and Iota UMa.
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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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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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Measures of photographed binaries with the eyepiece-method.
Abstract image available at:http://adsabs.harvard.edu/abs/1970A&A.....7..160H
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INHABITED SKY
