Precise Times of Minimum Light of Neglected Eclipsing Binaries
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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.
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Photoelectric Minima of Selected Eclipsing Binaries and Maxima of Pulsating Stars
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Close binary stars in ob-association regions i. preliminary investigation
We performed a sample of O- and B-eclipsing binary stars inOB-association regions and obtained the preliminary list of 147 binariesin 45 OB-association regions. We tried to elucidate the question whether(or not) the close binaries belong to corresponding OB-associations,from the commonness of their proper motions, radial velocities anddistances. Based on the completeness of the data,the binaries aredevided into three groups and the scheme for calculation of degree ofbelonging of stars to OB-associations is developed. Necessary data arenot available for nine systems and they are given in a specific table.For 12 cases, the binaries project onto the regions of two associations.We show that 33 (22.3%) close binary stars are members, 65 (43.9%) areprobable members and 39 (26.4%) are less probable members of theOB-associations. We find that 11 binaries belong to the Galaxybackground. The comparison of the distributions of orbital periods forthe binaries in OB-associations and for O-, B-binaries of the Galaxybackground shows their considerable differences in the vicinity of thetwo-day period.
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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
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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.
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UBV beta Database for Case-Hamburg Northern and Southern Luminous Stars
A database of photoelectric UBV beta photometry for stars listed in theCase-Hamburg northern and southern Milky Way luminous stars surveys hasbeen compiled from the original research literature. Consisting of over16,000 observations of some 7300 stars from over 500 sources, thisdatabase constitutes the most complete compilation of such photometryavailable for intrinsically luminous stars around the Galactic plane.Over 5000 stars listed in the Case-Hamburg surveys still lackfundamental photometric data.
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Dust shells around certain early-type stars with emission lines.
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The ``Mass Discrepancy'' for Massive Stars: Tests of Models Using Spectroscopic Binaries
Stellar evolutionary models are often used to infer a star's mass viaits luminosity, but empirical checks on the accuracy of the theoreticalmass-luminosity relation for very massive stars have been lacking. Thisis of particular concern given that modern atmosphere models yieldsystematically smaller masses for massive stars than do evolutionarymodels, with the discrepancy being a factor of 2 for Of stars. Weattempt to resolve this mass discrepancy by obtaining new,high-resolution optical data on seven early-type spectroscopic binaries:V453 Cyg, HD 191201, V382 Cyg, Y Cyg, HD 206267, DH Cep, and AH Cep. Ourstudy produces improved spectral subtypes for the components of thesesystems, which are crucial for evaluating their luminosities andlocations in the H-R diagram. Our radial velocity study utilizes ameasuring method that explicitly accounts for the effects of pairblending. We combine our new orbit solutions with existing data oninclinations and distances when available to compare the orbital masseswith evolutionary models, and we find good agreement in all cases wherethe stars are noninteracting. (The components of V382 Cyg and DH Cepfill their Roche lobes, and in both cases we find masses substantiallylower than the masses inferred from evolutionary tracks, suggesting thatsignificant material has been lost rather than transferred. We confirmthat this same trend exists for other systems drawn from theliterature.) Our own data extends to only 15 Mȯ, althoughphotometric inclination determinations for HD 191201 and HD 206267should prove possible and will provide examples of higher mass systems.We briefly discuss suitable systems from the literature and concludethat orbit solutions provide good agreement with the evolutionary modelsto 25 Mȯ. Beyond this, most known binaries either fill their Rochelobes or have other complications. We also discuss five systems forwhich our improved data and analysis failed to yield acceptable orbitsolutions: EO Aur, IU Aur, V640 Mon (Plaskett's star), LY Aur, and 29 UWCMa all remained intractable, despite improved data.
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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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The distribution of OB stars in the directions of the stellar associations AUR OB 1 and 2
Forty two OB stars have been observed with the space telescope Glazar at1640 A in an area of about 17 sq deg in the direction of the stellarassociations Aur OB 1 and 2. Twenty five of the observed stars of knownspectral type and with colorimetric data are assigned to four stargroups: a B association at a distance of 600 pc and three O associationsat distances of 1100, 2000 and 3000 pc respectively, designated Aur B0.6, Aur OB 1.1, Aur OB 2.0, and Aur OB 3.0. Fourteen stars of unknownspectral type should be OB or at least early-A-type stars, since theirimages were obtained on photographs taken with Glazar. The latestpossible spectral types of these stars and also of stars for which thespectral types are known only roughly are determined. There is a more orless uniform dust cloud in front of the dense parts of the three distantassociations, which introduces an extinction of about 3.5 mag at 1640 A.
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Predicting the Secondary Minima Depths and Spectra of the Main Components for the Dm-Type Eclipsing Variable Stars
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Close binaries observed polarimetrically
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A Study of the DM and SD Type Eclipsing Variables by Means of the Cluster Analysis Technique
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Massive close binaries with early-type components, observed characteristics.
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An Updated List of Eclipsing Binaries Showing Apsidal Motion
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2000 A UV imaging of a 6 deg diameter field around MU Aurigae
UV imagery of a 6 deg diameter field centered on Mu Aurigae in thegalactic plane was obtained with the SCAP 2000 experiment dedicated toan UV sky survey. Photometric UV magnitudes at 2000 A are given here formore than 500 stars detected in the field. A star-counting method isapplied to give a fine description of the interstellar matterdistribution up to 1000 pc. The mean space density for B8-A3 stars isderived. Stars with an UV excess are detected and spectralreclassification of some single or binary stars is suggested.
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Catalog of O-B stars observed with Tokyo Meridian Circle
A catalog of the O-B stars, selected from 'Blaauw-Parenago' list andRubin's catalog, has been compiled on the FK4 system by the observationsmade with Gautier 8-inch Meridian Circle at the Tokyo AstronomicalObservatory during the period, 1971 to 1979. It contains 1059 stars andwas compiled for the future establishment of high precision propermotions of O-B stars.
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The period distribution of unevolved close binary systems
Period distributions have been examined for various spectral types ofabout 600 (eclipsing and spectroscopic) close binaries, which are likelyto be substantially unevolved. The comparison with the previouscorresponding analyses of extensive (but heterogeneous) binary samplesallows a clarification of the extent of the evolutionary andobservational selection effects. Remarkably, this analysis reveals agreat deficiency of short period binaries (with periods corresponding tocase A mass transfer) in the whole spectral range. For the late spectraltypes, this result may be connected with postformation angular momentumloss caused by stellar wind magnetic braking; at least for the late Band A spectral range, a ready interpretation of this finding is thatclose binaries of corresponding periods and spectral types are rarelyformed.
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The mass-spectrum relation for main-sequence stars
A mass-spectrum relation is obtained for 240 main-sequence stars withknown masses; in several intervals of spectral class it differs markedlyfrom the analogous relations of Allen and Trimble. Its accuracy indetermining the masses of component stars of eclipsing binary systems ofvarious types from their spectra given in the General Catalog ofVariable stars III and supplements to it is estimated.
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Statistics of categorized eclipsing binary systems Lightcurve shapes, periods, and spectral types
The statistics of the light curve morphologies, eclipse depths, orbitalperiods, and spectral types of about 1000 eclipsing binary systems areexamined, after attempting to subdivide these binaries into variousbasic evolutionary categories. The applicability of statisticalcriteria, based on light curve morphologies and eclipse depths, for thecategorization of eclipsing binaries has been found more limited thanpreviously believed. In particular, EW-type light curves turn out to begood indicators of contact systems (though not conversely), while EA-and EB-type light curves have little physical significance. Moreover,the study reveals a strong deficit of short-period noncontact systems inthe whole spectral range, together with an underabundance of early-typecontact binaries (compared with the number of late-type contact pairs).Interestingly, the distribution of evolved Algol-type systems isshifted, on average, to periods longer than those of unevolved detachedsystems in the OB and early A spectral range (and to shorter periods inthe F spectral range).
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Radial velocities for early type stars in six galactic regions
Coudespectroscopy has been carried out for 353 stars of spectral typesB0-A0 and V magnitudes between 6.5 and 10.8 m, selected in six regions(three northern and three southern) close to the galactic plane at thegalactic longitudes 135, 175, 315 and 350 deg. The radial velocitieswere obtained by cross-correlating each spectrogram with a referencespectrogram giving an internal error of 1.4 km/s.
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Iterative methods for determination of parameters of spectroscopic binaries
The paper contains the description of iterative methods fordeterminations of geometric and physical parameters of spectroscopicbinaries, especially for computation of orbit plane inclination i andradii of components, which cannot be determined from observations. Thesemethods are based of some considerations given in the previous paper(Dworak 1975). The methods have been tested using data for eclipsingbinaries, taken from the catalogues of Batten et al. (1978) and Koch etal. (1970).
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Four-color and H-beta photometry for O-A0 type stars in three regions near the galactic equator
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1982A&AS...49..561W&db_key=AST
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Variable Stars in the Northern Luminous Stars Catalogues
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HD 208095 - Disappearance of the last of the overmassive detached binaries
The late B-type spectroscopic binary, HD 208095, is removed from thediminishing ranks of spectroscopic binaries with apparently anomalousmasses by means of analysis of a new set of spectrograms. The minimummasses (3.5 and 3.2 solar masses) are close to the masses expected forthe spectral types. The more massive star has the slightly earlier type.While the line widths in the spectrum of the cooler component of thisdetached system are consistent with equality of orbital and rotationalperiods, the lines of the hotter component are considerably broader.
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A Photoelectric Lightcurve and Elements of the Eclipsing Binary Eo-Aurigae
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First supplement to the catalogue of modern lightcurve synthesis photometric solutions of close binary systems
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Comparison between the observations and evolutionary calculations for massive close binary systems
With regard to OB stars, members of close binaries, estimates are madefor mass loss rate due to radiation driven stellar winds, the fractionof the expelled mass leaving the system, and the fraction of the lostangular momentum. Observations reveal that massive systems in the postRoche lobe overflow stage are not immediately converted into Wolf-Rayetsystems but pass through a new 'normal' OB stage. Furthermore, due tostellar wind mass loss the mass ratio of nonevolved systems willincrease; consequently, most of the systems just before Roche lobeoverflow (that is, at the end of core hydrogen burning) will have a massratio larger than 0.7.
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INHABITED SKY
