Absolute Parameters for Eight Eclipsing Binaries in the Large Magellanic Cloud: The Mass-Luminosity Relation
A simultaneous light and radial velocity analysis of eight LargeMagellanic Cloud (LMC) eclipsing binaries is presented. Combiningspectroscopic observations obtained with UVES at the ESO Very LargeTelescope and light curves available from the MACHO and OGLE databases,accurate masses and radii for the binary components, along with theirspectral types and luminosities, are derived. These determinations allowus to construct the first mass-luminosity relation for late O and earlyB type stars in the LMC. This mass-luminosity relation looks verysimilar to that of the Milky Way, in spite of the differentmetallicities. The good agreement achieved in the comparison with recenttheoretical isochrones is encouraging regarding the reliability of starmodels up to 20 Msolar.Based on observations obtained at the European Southern Observatory,Paranal, with VLT UT2 (Kueyen); ESO programs 68.D-0328(A) and70.D-0191(A).
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Fundamental Properties and Distances of Large Magellanic Cloud Eclipsing Binaries. IV. HV 5936
We have determined the fundamental properties and distance of a fourtheclipsing binary (EB) system in the Large Magellanic Cloud, HV 5936(~B0.5 V + ~B2 III). As in our previous studies, we combine``classical'' EB light-curve and radial velocity curve analyses withmodeling of the UV/optical spectral energy distribution of HV 5936 toproduce a detailed characterization of the system. In this paper, wealso include an analysis of the high-resolution optical absorption linespectra of the binary components. We find HV 5936 to be an Algol-classsystem, in which the masses of the primary and secondary stars haveevolved via mass transfer to their current values of 11.6 and 4.7Msolar, respectively. The properties of the primary star areindistinguishable from those of a ``normal'' star of the same currentmass. The secondary is found to be overluminous for its current mass andexhibits a factor of 2 enhancement in its surface He abundance. Theseresults are compatible with case A mass exchange occurring during thecore hydrogen-burning phase of the current secondary. The distancederived to the system, 43.2+/-1.8 kpc, implies a distance of ~44.3 kpcto the optical center of the LMC. This is several kiloparsecs closerthan found in our analyses of other systems, and we suggest that HV 5936lies ``above'' the LMC disk. This is supported by the very lowinterstellar H I column density and low E(B-V) found for the system-bothof which are consistent with expected Milky Way foreground material-andmay be associated with HV 5936's location near the LMC supergiant shellLMC 4.Based on observations with the NASA/ESA Hubble Space Telescope, obtainedat the Space Telescope Science Institute, which is operated by theAssociation of Universities for Research in Astronomy (AURA), Inc.,under NASA contract NAS 5-26555.
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Fundamental Properties and Distances of the Large Magellanic Cloud from Eclipsing Binaries. II. HV 982
We have determined the distance to a second eclipsing binary (EB) systemin the Large Magellanic Cloud, HV 982 (~B1 IV-V+~B1 IV-V). Themeasurement of the distance-among other properties of the system-isbased on optical photometry and spectroscopy and space-based UV/opticalspectrophotometry. The analysis combines the ``classical'' EB study oflight and radial velocity curves, which yields the stellar masses andradii, with a new analysis of the observed energy distribution, whichyields the effective temperature, metallicity, and reddening of thesystem plus the distance ``attenuation factor,'' essentially(radius/distance)2. Combining the results gives the distanceto HV 982, which is 50.2+/-1.2 kpc. This distance determination consistsof a detailed study of well-understood objects (B stars) in awell-understood evolutionary phase (core H burning). The results areentirely consistent with-but do not depend on-stellar evolutioncalculations. There are no ``zero-point'' uncertainties as, for example,with the use of Cepheid variables. Neither is the result subject tosampling biases, as may affect techniques that utilize whole stellarpopulations, such as red giant branch stars. Moreover, the analysis isinsensitive to stellar metallicity (although the metallicity of thestars is explicitly determined), and the effects of interstellarextinction are determined for each object studied. After correcting forthe location of HV 982, we find an implied distance to the opticalcenter of the LMC's bar of dLMC=50.7+/-1.2 kpc. This resultdiffers by nearly 5 kpc from our earlier result for the EB HV 2274,which implies a bar distance of 45.9 kpc. These results may eitherreflect marginally compatible measures of a unique LMC distance or,alternatively, suggest a significant depth to the stellar distributionin the LMC. Some evidence for this latter hypothesis is discussed. Basedon observations with the NASA/ESA Hubble Space Telescope, obtained atthe Space Telescope Science Institute, which is operated by theAssociation of Universities for Research in Astronomy, Inc., under NASAcontract NAS 5-26555.
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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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The proper motions of fundamental stars. I. 1535 stars from the Basic FK5
A direct combination of the positions given in the HIPPARCOS cataloguewith astrometric ground-based catalogues having epochs later than 1939allows us to obtain new proper motions for the 1535 stars of the BasicFK5. The results are presented as the catalogue Proper Motions ofFundamental Stars (PMFS), Part I. The median precision of the propermotions is 0.5 mas/year for mu alpha cos delta and 0.7mas/year for mu delta . The non-linear motions of thephotocentres of a few hundred astrometric binaries are separated intotheir linear and elliptic motions. Since the PMFS proper motions do notinclude the information given by the proper motions from othercatalogues (HIPPARCOS, FK5, FK6, etc.) this catalogue can be used as anindependent source of the proper motions of the fundamental stars.Catalogue (Table 3) is only available at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strastg.fr/cgi-bin/qcat?J/A+A/365/222
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Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions
The FK6 is a suitable combination of the results of the HIPPARCOSastrometry satellite with ground-based data, measured over more than twocenturies and summarized in the FK5. Part I of the FK6 (abbreviatedFK6(I)) contains 878 basic fundamental stars with direct solutions. Suchdirect solutions are appropriate for single stars or for objects whichcan be treated like single stars. From the 878 stars in Part I, we haveselected 340 objects as "astrometrically excellent stars", since theirinstantaneous proper motions and mean (time-averaged) ones do not differsignificantly. Hence most of the astrometrically excellent stars arewell-behaving "single-star candidates" with good astrometric data. Thesestars are most suited for high-precision astrometry. On the other hand,199 of the stars in Part I are Δμ binaries in the sense ofWielen et al. (1999). Many of them are newly discovered probablebinaries with no other hitherto known indication of binarity. The FK6gives, besides the classical "single-star mode" solutions (SI mode),other solutions which take into account the fact that hidden astrometricbinaries among "apparently single-stars" introduce sizable "cosmicerrors" into the quasi-instantaneously measured HIPPARCOS proper motionsand positions. The FK6 gives in addition to the SI mode the "long-termprediction (LTP) mode" and the "short-term prediction (STP) mode". TheseLTP and STP modes are on average the most precise solutions forapparently single stars, depending on the epoch difference with respectto the HIPPARCOS epoch of about 1991. The typical mean error of anFK6(I) proper motion in the single-star mode is 0.35 mas/year. This isabout a factor of two better than the typical HIPPARCOS errors for thesestars of 0.67 mas/year. In the long-term prediction mode, in whichcosmic errors are taken into account, the FK6(I) proper motions have atypical mean error of 0.50 mas/year, which is by a factor of more than 4better than the corresponding error for the HIPPARCOS values of 2.21mas/year (cosmic errors included).
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Five-colour photometry of OB-stars in the Southern Hemisphere
Observations of OB-stars, made in 1959 and 1960 at the Leiden SouthernStation near Hartebeespoortdam, South Africa, with the VBLUW photometerattached to the 90 cm light-collector, are given in this paper. They arecompared with photometry obtained by \cite[Graham (1968),]{gra68}\cite[Walraven & Walraven (1977),]{wal77} \cite[Lub & Pel(1977)]{lub77} and \cite[Van Genderen et al. (1984).]{gen84} Formulaefor the transformation of the present observations to those of\cite[Walraven & Walraven (1977)]{wal77} and \cite[Lub & Pel(1977)]{lub77} are given. Table 4 is only available in electronic format the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) orvia http://cdsweb.u-strasbg.fr/Abstract.html
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The Distribution of Dust Clouds in the Interstellar Medium
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJ...457..764D&db_key=AST
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The ROSAT all-sky survey catalogue of optically bright OB-type stars.
For the detailed statistical analysis of the X-ray emission of hot starswe selected all stars of spectral type O and B listed in the Yale BrightStar Catalogue and searched for them in the ROSAT All-Sky Survey. Inthis paper we describe the selection and preparation of the data andpresent a compilation of the derived X-ray data for a complete sample ofbright OB stars.
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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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Second astrolabe catalogue of Santiago.
Positions for 350 FK5 and 164 FK5 Extension stars as determined with theDanjon astrolabe of Santiago and differences astrolabe-catalogue aregiven for Equinox J2000.0 and for the mean observation epoch of eachstar. The average mean error in alpha is +/-0.005s and +/-0.07" indelta. The mean epoch of observation of the catalogue is J1979.96.
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The distribution of interstellar dust in the solar neighborhood
We surveyed the IRAS data base at the positions of the 1808 O6-B9.5stars in The Bright Star Catalog for extended objects with excessemission at 60 microns, indicating the presence of interstellar dust atthe location of the star. Within 400 pc the filling factor of theinterstellar medium, for dust clouds with a density greater than 0.5/cucm is 14.6 + or - 2.4%. Above a density of 1.0/cu cm, the densitydistribution function appears to follow a power law index - 1.25. Whenthe dust clouds are mapped onto the galactic plane, the sun appears tobe located in a low-density region of the interstellar medium of widthabout 60 pc extending at least 500 pc in the direction of longitudes 80deg - 260 deg, a feature we call the 'local trough'.
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Santiago Fundamental Catalogue - A catalogue of 1105 FK5 stars (equinox J2000.0)
The positions in right ascension and declination of 1105 FK5 stars,observed with a Meridian Circle during the period 1979 to 1991, aregiven. The average mean square error of a position, for the wholecatalog, is +/- 0.009 s in right ascension and +/- 0.10 arcsec indeclination. The mean epoch of the catalog is 1983.148.
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Santiago declination catalogue. II - A declination catalogue of 493 FK5 stars (equinox J2000.0)
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1991A&AS...90..109C&db_key=AST
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Effective temperature and gravity from c(0) and beta indices for B-type stars
A sample of nonsupergiant B-type stars of solar chemical composition hasbeen analyzed for T(eff) and gravity differences due to the use of c(0)and beta indices from different photometric grids. The Moon andDworetsky (1985) grid, as well as an extension of the grid, are found toyield T(eff)s closer to those derived with other methods than the Lesteret al. (1986) grid; in addition, the former grid yields gravities thatare closer to values in the literature than the latter grid. A modifiedversion of the TEFFLOGG code of Moon (1985), which employs polynomialfunctions of the Stromgren indices, yields both T(eff) and gravity forthe present sample of B-type stars.
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Broad-band photometry of selected southern ultraviolet-bright stars.
Not Available
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Physical data of the fundamental stars.
Not Available
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Catalogue of i and w/w crit values for rotating early type stars
Not Available
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The third astrolabe catalogue at Valinhos
Individual Delta alpha and Delta beta corrections have been obtained for109 FK4 and FK4-Supplement stars, based on 45-deg zenith observationsmade with the Danjon astrolabe at Valinhos. The observations were madebetween December 1983 and December 1986, and they cover the declinationzone of + 20 deg to -65 deg. The present results have been compared withdata for the common stars of the First and Second Astrolabe Cataloguesat Valinhos, which were based on 30-deg zenith observations.
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Santiago declination catalogue - A declination catalogue of 412 FK4 stars (equinox 1950.0)
This catalog contains the positions in declination, of 412 FK4 stars.The observations were carried out with the Repsold Meridian Circle atCerro Calan National Astronomical Observatory, during the period1963-1968. The average mean square error of one observation (for thewhole catalog) is + or - 0.13 arcsec. The mean epoch of observation ofthe catalog is 1965.75.
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A catalog of ultraviolet interstellar extinction excesses for 1415 stars
Ultraviolet interstellar extinction excesses are presented for 1415stars with spectral types B7 and earlier. The excesses with respect to Vare derived from Astronomical Netherlands Satellite (ANS) 5-channel UVphotometry at central wavelengths of approximately 1550, 1800, 2500, and3300 A. A measure of the excess extinction in the 2200-A extinction bumpis also given. The data are valuable for investigating the systematicsof peculiar interstellar extinction and for studying the character of UVinterstellar extinction in the general direction of stars for which theextinction-curve shape is unknown.
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Observed and computed spectral flux distribution of non-supergiant O9-G8 stars. III - Determination of T(eff) for the stars in the Breger Catalogue
The effective temperatures and angular diameters of nonsupergiant O9-G8stars are determined from visible spectrophotometry. The results, whichrefer to 302 stars included in the Breger Catalogue, are derived fromthe comparison between the observed flux distributions and thepredictions of Kurucz's models (1979). The uncertainties to be expectedin individual results are discussed; their sizes are of the order of 5percent in effective temperature and 10 percent in angular diameter.
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The local system of early type stars - Spatial extent and kinematics
Published uvby and H-beta photometric data and proper motions arecompiled and analyzed to characterize the structure and kinematics ofthe bright early-type O-A0 stars in the solar vicinity, with a focus onthe Gould belt. The selection and calibration techniques are explained,and the data are presented in extensive tables and graphs and discussedin detail. The Gould belt stars of age less than 20 Myr are shown togive belt inclination 19 deg to the Galactic plane and node-lineorientation in the direction of Galactic rotation, while the symmetricaldistribution about the Galactic plane and kinematic properties (purecircular differential rotation) of the belt stars over 60 Myr oldresemble those of fainter nonbelt stars of all ages. The unresolveddiscrepancy between the expansion observed in the youngest nearby starsand the predictions of simple models of expansion from a point isattributed to the inhomogeneous distribution of interstellar matter.
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The galactic reddening law - The evidence from uvby-beta photometry of B stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&A...142..189T&db_key=AST
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A survey of ultraviolet objects
An all-sky survey of ultraviolet objects is presented together with astatistical analysis that leads to the conclusion that there is asignificantly higher population of hot subdwarfs lying below themain-sequence than hitherto thought. The distribution of all ultravioletobjects, main sequence ultraviolet objects, and MK unclassifiedultraviolet objects are shown in galactic coordinates, and the absolutemagnitudes and color-color diagrams for these groups are presented.Scale heights are derived, giving values similar to planetary nebulaefor the hottest groups.
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Picture gallery - A structured presentation of OAO-2 photometric data supported by OAO-2 spectrophotometric data and UBV, ANS and TD1 observations
Graphs are presented for the stellar fluxes of 531 stars in the5500-1330 A wavelength range, which have been divided into 52 categorieson the basis of spectral types. The merging of medium band interferencefilter photometry, UBV photometry, ANS photometry and TD1 fluxes, aswell as the ordering of the objects, should prove helpful in studies ofinterstellar reddening, luminosity effects, bandwidth effects, andcomparisons with model stellar atmospheres. The agreement between thevarious UV photometric systems for early-type stars is generally betterthan 0.10 mag. A list of stars whose photometric properties indicatestellar or interstellar anomalies is also provided.
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Geneva photometric boxes. II - The reddening towards the galactic poles
It is noted that photometric boxes allow a very accurate estimation ofindividual reddenings for B- and early A-type stars. A catalog of 129stars with galactic latitudes higher than 30 deg is given. A small butsignificant reddening is seen in the direction of both the northern andsouthern galactic poles: E(B-V) approximately 0.04.
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Ultraviolet photometry from the Orbiting Astronomical Observatory. XXXIV - Filter photometry of 531 stars of diverse types
Ultraviolet magnitudes for 531 stars observed with the WisconsinExperiment Package on OAO 2 are tabulated. It is noted that these dataconstitute a subset of the OAO 2 data on file at the National SpaceScience Data Center. The tabulation contains previously published dataall reduced to a uniform magnitude system. It is pointed out that theobservations were obtained with the medium band interference filterphotometers. Eleven magnitudes are given designated by their centroidwavelengths.
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Ultraviolet photometry from the Orbiting Astronomical Observatory. XXXVIII - A second atlas of ultraviolet stellar spectra
Ultraviolet stellar spectra are presented for 132 stars in the spectralregion from 1200 to 1850 A and 34 stars in the region from 1800 to 3600A in a graphical and tabular form. The spectra represent a subset of OAO2 spectrometer data on file at the National Space Science Data Center.The monochromatic flux is given in units of ergs/sq cm s A with aspectral resolution of about 12 A in the region from 1850 to 1160 A andof about 22 A in the region from 3600 to 1800 A.
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Space velocities and ages of nearby early-type stars
Photometric distances and space velocities have been calculated for 458B0-A0 stars with apparent magnitudes not exceeding 6.5. UsingStromgren's ubvy-beta photometry the effective temperature and theposition in bolometric magnitude over the zero-age main sequence of thestars were derived. These quantities were used to obtain age and massfor 423 of the stars by interpolation in the models of stellar evolutionfor the chemical composition (X Z) = (0.7, 0.03). A relation forderiving interstellar reddening for normal stars in the intermediategroup is given.
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INHABITED SKY
