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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V505 Mon - An early-type binary with a disk
New spectra of the eclipsing binary V505 Mon (usually classified as B5Ib) were obtained in the optical and UV regions. Only spectral lines ofone component are visible, with K = 93 km s-1. According toarguments based on the extent of the disk the mass ratio might be about0.30. The star with the visible spectral lines would then have a mass of2.3, the other component of 7.7 Msun, i.e. their supergiantnature can be ruled out. The distance to the system appears to be about1 kpc. Together with published photometric data, the spectroscopyprovides clear evidence for the presence of a disk around the secondarycomponent. The profiles of the C II 1335/6 doublet lines are used toderive the rotational velocity of the disk. The structure of the diskcan be characterized by a central ionized zone surrounded by neutralouter parts. Additional matter of cloudy nature has to be present, andboth components are embedded in an extended atmosphere. Abundance ofcarbon was found to be very low. Similarity with some othernon-eclipsing binaries is discussed. Based on observations collected atthe European Southern Observatory, La Silla, Chile, and at theGerman-Spanish Observatory, Calar Alto, Spain.
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Identifications for Wachmann's Variables in SA 98
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Catalogue of H-alpha emission stars in the Northern Milky Way
The ``Catalogue of Stars in the Northern Milky Way Having H-alpha inEmission" appears in Abhandlungen aus der Hamburger Sternwarte, Band XIin the year 1997. It contains 4174 stars, range {32degr <= l() II< 214degr , -10degr < b() II < +10degr } having the Hαline in emission. HBH stars and stars of further 99 lists taken from theliterature till the end of 1994 were included in the catalogue. We givethe cross-identification of stars from all lists used. The catalogue isalso available in the Centre de Données, Strasbourg ftp130.79.128.5 or http://cdsweb.u-strasbg.fr and at the HamburgObservatory via internet.
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Long-term visual spectrophotometric behaviour of Be stars. II. Correlations with fundamental stellar parameters and interpretation
The long-term visual spectrophotometric (SPh) behaviour of Be stars as afunction of fundamental stellar parameters is studied. Some previous SPhresults obtained by other authors are confirmed. Moreover, a tendencyfor temperature and aspect angle dependency of SPh variations is found.From the characteristics of visual SPh behaviour in Be stars we deriveconstraints for models of regions in circumstellar envelopes where thevisual continuum spectrum is formed: (i) The SPh emission and absorptionphases should not imply preferential aspect angles, as they can bothappear whatever the stellar inclination. This phenomenon cannot bealways accounted for by strongly flattened circumstellar envelopes; (ii)Radii of the visible continuum forming regions cannot be larger than afew R_*; (iii) Electron densities of these regions should not exceed N_e~ 10(13) cm(-3) ; (iv) Electron temperature of circumstellar layersproducing the SPh emission phases compare with the stellar Balmercontinuum radiation temperature and it is much lower in those producingthe SPh absorption phases. Three scenarios were studied to produce theobserved characteristics of emissions in the V magnitude and in thesecond component of Balmer discontinuity (Delta D) during the SPhemission phases: (a) expansion of a massive circumstellar shell thatpreserves circumstellar envelope flattening; (b) expansion of acircumstellar shell which increases the global flattening, so that adisc-like structure is formed; (c) continuous mass ejection thatincreases the storage of mass in a constant volume with a givenflattening. Mechanisms (a) and (b) produce a double valued (DeltaV,Delta D) SPh relation, while (c) produces a single valued relation.Only mechanisms (a) and (c) can easily produce the observed amounts ofemission Delta V and Delta D without violating the modeling constraintsfrom (i) to (iv) imposed by observations. The model SPh slopes of (DeltaV,Delta D) show the global sin i and T_eff observed dependencies. Thescenarios used to describe the double valued (Delta V,Delta D) suggestanother possible way how to build up circumstellar envelopes around Bestars.
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High-speed photometry of the star HR 2517.
Not Available
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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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Long-term visual spectrophotometric behaviour of Be stars
The long-term spectrophotometric variations of 49 Be stars are studiedusing the U and V magnitudes of the UBV system, the total Balmerdiscontinuity D and the visible gradient Phi _rb. BCD spectrophotometricand photometric data in five different photometric systems, obtained inmost cases since 1950 and reduced to the BCD system, were used. The(U,D), (V,D), (Phi _rb,D) and (Phi _rb,V) correlations obtained differfrom star to star and they can be single or double-valued. They differclearly for Be phases or Be-shell phases. Be stars with small Vsin ishowing the ``spectrophotometric shell behaviour'': D > D_*, werefound. This finding implies either that strongly flattened models ofcircumstellar envelopes are in doubt for these stars, or that not all Bestars are rapid rotators. Comparison of observed variations with thosepredicted for model Be stars with spherical circumstellar envelopes ofvariable densities and dimensions implies that spectrophotometricpatterns of Be phases are due to circumstellar envelopes in low opacityregimes, while those of spectrophotometric shell phases are due tocircumstellar envelopes in high opacity regimes. In a given star, theenvelope regions responsible for the observed variations of D and Phi_rbin spectrophotometric shell phases seem to be smaller and denser thanthose producing the observed variations of these parameters inspectrophotometric Be phases. The high positive RV found in strong shellphases might favor the formation of compact circumstellar layers nearthe star. Figure 6 is only available in electronic form at CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Catalogue of stars in the northern Milky Way having H-alpha in emission
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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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A flare event on HR2517
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Differential UVBY photometry of southern Be stars. Highlights from the recent analysis of LTPV data.
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The Massive Eclipsing Be Star Binary V505 Monocerotis
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Long-term photometry of variables at ESO. I - The first data catalogue (1982-1986)
This paper presents the catalog of photometric data in the Stromgrensystem obtained during the first four years (October 1982 - September1986) of the Long-Term Photometry of Variables (LTPV) program at ESO.The data are available in computer-readable form.
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Amateur Variable Star Observing in Japan
Activities and publications of various astronomical groups in Japan aredescribed.
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Massive close binaries with early-type components, observed characteristics.
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Eclipsing binaries, Lacerta to Orion, in 1969-1986
Photoelectric and visual observations of 37 known and suspectedeclipsing binaries are discussed. Revised light elements are derived forHP Lyr, V839 Oph and V530 Ori. WZ Leo is probably constant. Both of thealternative periods given in the literature for UW Ori appear to beincorrect. The period of V543 Ori is confirmed to be 52.42d., and not26.21d.
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Empirical temperature calibrations for early-type stars
Three temperature calibrations of suitable photometric quantities havebeen derived for O and B stars. A sample of 120 stars with reliableT(eff.) determinations has been used for establishing each calibration.The different calibrations have been critically discussed and compared.Temperature determinations for 1009 program stars have been obtainedwith an accuracy of the order of 10 percent.
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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.
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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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Photoelectric Photometry of the Eclipsing Binary V505-MONOCEROTIS
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985CoSka..13...75C&db_key=AST
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Comments on V505 MON - One of the most massive binaries
The results of Stagni et al. (1982) for the dimensions of V505 Mon arediscussed with regard to stellar and close binary evolution. The HRDposition of each component is determined and compared to possiblepositions of theoretical stars of comparable mass in the HRD accordingto various evolutionary computations. These theoretical componentsindicate masses for the components which are incompatical with themasses derived by Stagni et al. and are also impossible for physicalreasons.
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Variable Stars in the Northern Luminous Stars Catalogues
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V 505 MON - One of the most massive binaries
Spectroscopic and orbital features of the bright binary star V 505 Monare reported. A total of 59 spectrograms were made of the object fromDec. 1969-76. Petrie's lines were employed to determine the radialvelocities of the pair. A 53.7805 day period was observed, together witha system velocity within 3 km/sec of 32 km/sec, an eccentricity within0.5 of 0.06, a periastron angle of component 1 of plus or minus 34 degof 15 deg. The periastron epoch of component 1 was 2441424.03, close tothe ascending node epoch. The semi-amplitude of component 1 was within 4km/sec of 83 km/sec, while the semi-amplitude of component 2 was within11 km/sec of -155 km/sec. The mass function of the primary was within 4of 20 solar masses, the secondary, within 0.4 of 3.2 solar masses. Thesystem appeared well-detached. H-alpha emission was recorded in fourphases.
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Search for the Period of the Binary Shell Star V505 Monocerotis
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Contact binaries . III. Early-type systems.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978AJ.....83..288E&db_key=AST
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The value of R in Monoceros
Recent photometric and spectroscopic observations are used inconjunction with other data for early-type stars in northern Monocerosin order to investigate the local value of R (the ratio of total toselective extinction). From a variable-extinction analysis, it isconcluded that a ratio of approximately 3.2 is appropriate for thegeneral interstellar extinction in this region and that there is noevidence here for the existence of local anomalies. The two majorassociations Mon OB 1 and Mon OB 2 are clearly delineated and are foundto exhibit properties typical of such young stellar groups. Derivedproperties for a few interesting stars are presented.
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Quatre nouvelles etoiles B a emission.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974A&A....33..473B&db_key=AST
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Identification List of the New Variable Stars Nominated in 1968
Not Available
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INHABITED SKY
