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HD 203470


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Photoelectric Minima of Selected Eclipsing Binaries and Maxima of Pulsating Stars
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Photoelectric Minima of Selected Eclipsing Binaries and Maxima of Pulsating Stars
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A catalogue of eclipsing variables
A new catalogue of 6330 eclipsing variable stars is presented. Thecatalogue was developed from the General Catalogue of Variable Stars(GCVS) and its textual remarks by including recently publishedinformation about classification of 843 systems and making correspondingcorrections of GCVS data. The catalogue1 represents thelargest list of eclipsing binaries classified from observations.

Automatic classification of eclipsing binaries light curves using neural networks
In this work we present a system for the automatic classification of thelight curves of eclipsing binaries. This system is based on aclassification scheme that aims to separate eclipsing binary systemsaccording to their geometrical configuration in a modified version ofthe traditional classification scheme. The classification is performedby a Bayesian ensemble of neural networks trained with Hipparcos data ofseven different categories including eccentric binary systems and twotypes of pulsating light curve morphologies.

Basic physical properties of the low-temperature contact binary system V781 Tau and the near-contact binary system V836 Cyg
We present a detailed photometric study of the low-temperature contactbinary V781 Tau, and the near-contact binary V836 Cyg. We have combinedthe parameters obtained from the light-curve analysis with those foundby the spectral studies and we have determined the orbital and physicalparameters of the stars. We have collected the times of the mid-eclipsesobtained so far and combined with the times obtained in this study. Byanalysing all these data we determined the mass transfer rate from themassive star to the less massive one for V781 Tau, and from the lessmassive component to the massive one in the case of V836 Cyg. Finally,we have compared the results obtained for V781 Tau and for V836 Cyg withsimilar systems.

Photoelectric Minima of Some Eclipsing Binary Stars
We present 70 minima times of 35 eclipsing binaries.

CCD Times of Minima of Selected Eclipsing Binaries
682 CCD minima observations of 259 eclipsing binaries made mainly byauthor are presented. The observed stars were chosen mainly fromcatalogue BRKA of observing programme of BRNO-Variable Star Section ofCAS.

New Times of Minima of Some Selected Eclipsing Binary Systems
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Times of Minima for Neglected Eclipsing Binaries in 2002
We present several CCD minima observations of eclipsing binaries.

The First Eclipsing Binary Observations at the Ulupinar Astrophysics Observatory
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New Times of Minima of Eclipsing Binary Systems
We present several photoelectric minima observations of 3 eclipsingbinaries.

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

Stars with the Largest Hipparcos Photometric Amplitudes
A list of the 2027 stars that have the largest photometric amplitudes inHipparcos Photometry shows that most variable stars are all Miras. Thepercentage of variable types change as a function of amplitude. Thiscompilation should also be of value to photometrists looking forrelatively unstudied, but large amplitude stars.

Do the physical properties of Ap binaries depend on their orbital elements?
We reveal sufficient evidence that the physical characteristics of Apstars are related to binarity. The Ap star peculiarity [represented bythe Δ(V1-G) value and magnetic field strength] diminishes witheccentricity, and it may also increase with orbital period(Porb). This pattern, however, does not hold for largeorbital periods. A striking gap that occurs in the orbital perioddistribution of Ap binaries at 160-600d might well mark a discontinuityin the above-mentioned behaviour. There is also an interestingindication that the Ap star eccentricities are relatively lower thanthose of corresponding B9-A2 normal binaries for Porb>10d.All this gives serious support to the pioneering idea of Abt &Snowden concerning a possible interplay between the magnetism of Apstars and their binarity. Nevertheless, we argue instead in favour ofanother mechanism, namely that it is binarity that affects magnetism andnot the opposite, and suggest the presence of a newmagnetohydrodynamical mechanism induced by the stellar companion andstretching to surprisingly large Porb.

Photoelectric and CCD times of minima of 19 eclipsing binary systems
We present several photoelectric and unfiltered CCD minima observationsof 19 eclipsing binaries. Most of them are apsidal motion stars (or atleast candidate ones).

Photoelectric minima of 30 eclipsing binary systems
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Near-Contact Binary Systems in the ROSAT All-Sky Survey
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJ...461..951S&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.

Near-contact binaries
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Photometric Investigation of the Semidetached System V836 Cygni
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Period changes of early-type eclipsing binaries
Eclipsing binaries with short periods are an important source of ourknowledge about the evolution of close binary systems. New photoelectrictimings of minima of the five short period early-type eclipsing binariesEG Cep, GK Cep, GO Cyg, V836 Cyg, and V1073 Cyg are presented here.Their period changes and current light elements are discussed.

Radial-velocity measurements. III - Ground observations accompanying the HIPPARCOS satellite observation program: Measurements of the radial velocities of 391 stars in 12 fields
The radial velocities of 391 stars, obtained with the Fehrenbachobjective prism associated to the Schmidt telescope of the Observatoirede Haute-Provence are presented. These stars belong to fields speciallychosen for containing several Hipparcos input catalog star members. Eachfield is presented independently. The list includes HD and BDidentifiers when available, 1950 coordinates, spectral type, and B and Vmagnitudes as they appear in the CSI catalog, the radial velocity, theprobable error, the number of independent measurements and commentariessuch as known radial velocity and their origin.

Light curve analysis and parameter study of the EB-type eclipsing binary V 836 Cygni
Extensive UBV photometry is used to study the EB-type short-periodeclipsing binary, V 836 Cygni. The Simplex method of parameteroptimization is applied to the Wilson-Devinney (1971) model approach,showing that the corresponding global minimum of delta(fit) is onlymarginally pronounced, allowing the lightcurve to be fitted over a widerange of parameters. This is overcome by evaluating the four-colorStromgren observations of Hilditch and Hill (1975). The results suggestthat the system has evolved through the stage of rapid mass exchangewith mass-ratio reversal.

Statistical investigation of chemically peculiar stars. VI. Eclipsing binaries.
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Spectroscopic binaries - 15th complementary catalog
Published 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.

Eclipsing binaries, Cygnus to Hydra, in 1972-1985
Photoelectric and visual observations of 40 known and suspectedeclipsing binaries are discussed. Revised light elements are derived forthree systems. The period of V450 Her should possibly be doubled fromabout 0.9d to about 1.8d. Secondary minimum has been detected in DI Hya.

A study of the O'Connell effect in the light curves of eclipsing binaries
In the present consideration of O'Connell's (1951) study of the lightcurve asymmetry between outside eclipse maxima, using UBV photoelectricdata, parametric and nonparametric methods indicate significantcorrelations in at least one color between the size of the asymmetry, onthe one hand, and several additional parameters. These include: thecolor index of the asymmetry, the relative sizes of the hotter andsmaller components, and their distortion, the relative separation of thestars, and the logarithm of the period. The present study data arecharacterized by lower mean amplitudes and a much more even distributionof the asymmetry, with respect to sign, than that of O'Connell, andthere is a tendency for the brighter maximum to be redder, contrary toO'Connell's results. More than one mechanism for the O'Connell effect issuggested.

The S201 far-ultraviolet imaging survey. II - A field in Cygnus
Far-ultraviolet imagery of a region in Cygnus, a 20 deg diameter fieldcentered near (1950) R. A. 21 h 31.2 m decl. +37 deg 25 arcmin, wasobtained by the S201 far-ultraviolet camera during the Apollo 16mission. In a 10 minute exposure covering the 1250-1600 A wavelengthrange (effective wavelength 1400 A), 730 star images can be detected,corresponding to a limiting ultraviolet magnitude of about m (1400) =10. Assuming nominal interstellar extinction values in this region nearthe galactic plane, this result corresponds to the detection of A0 Vstars to a distance of 300 pc and of B0 V stars to 1500 pc.Uncertainties in spectral classification and interstellar extinction forindividual objects are probably more significant than calibration ormeasurement errors. Most of the objects detected are identified withstars in the Smithsonian Astrophysical Observatory Star Catalog (1966),or the Catalog of Stellar Identifications (1979) or both, but 87 objectsremain unidentified (or are identified with late-type stars).

Photoelectric Minima of Eclipsing Binaries
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The Spectroscopic Orbit of the Short-Period Eclipsing Binary V836-CYGNI
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Observation and Astrometry data

Constellation:Cygne
Right ascension:21h21m23.59s
Declination:+35°44'10.6"
Apparent magnitude:8.763
Distance:240.385 parsecs
Proper motion RA:13
Proper motion Dec:-6.2
B-T magnitude:8.841
V-T magnitude:8.77

Catalogs and designations:
Proper Names
HD 1989HD 203470
TYCHO-2 2000TYC 2715-262-1
USNO-A2.0USNO-A2 1200-17761111
HIPHIP 105437

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