Effective temperature scale and bolometric corrections from 2MASS photometry
We present a method to determine effective temperatures, angularsemi-diameters and bolometric corrections for population I and II FGKtype stars based on V and 2MASS IR photometry. Accurate calibration isaccomplished by using a sample of solar analogues, whose averagetemperature is assumed to be equal to the solar effective temperature of5777 K. By taking into account all possible sources of error we estimateassociated uncertainties to better than 1% in effective temperature andin the range 1.0-2.5% in angular semi-diameter for unreddened stars.Comparison of our new temperatures with other determinations extractedfrom the literature indicates, in general, remarkably good agreement.These results suggest that the effective temperaure scale of FGK starsis currently established with an accuracy better than 0.5%-1%. Theapplication of the method to a sample of 10 999 dwarfs in the Hipparcoscatalogue allows us to define temperature and bolometric correction (Kband) calibrations as a function of (V-K), [m/H] and log g. Bolometriccorrections in the V and K bands as a function of T_eff, [m/H] and log gare also given. We provide effective temperatures, angularsemi-diameters, radii and bolometric corrections in the V and K bandsfor the 10 999 FGK stars in our sample with the correspondinguncertainties.
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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 UV spectrum as a signature of the Lambda Bootis character
The spectra of all the stars previously classified as Lambda Bootisstars and observed by the IUE satellite at low resolution, in the shortwavelength range, are analyzed. The usefulness of this spectral rangefor classifying the Lambda Boo stars is shown; the UV criteria used todistinguish the Lambda Boo stars from other metal-deficient stars areselected and applied. The origin of the Lambda Boo phenomenon is not yetclear (Baschek and Slettebak, 1988) and a careful selection of thecandidates is the first step for a clear definition of the theoreticalproblem. From the present study, it turns out that only seven out of the19 candidates can be assigned to the Lambda Boo group, while for theother stars the previous classification must be considered eroneous. Thepeculiarities of the other metal-deficient, but not Lambda Boo, starsare discussed.
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Catalog of mean stellar radial velocities (catalog on magnetic tape)
A catalog of the mean radial velocities for 6451 Galactic stars isdescribed, which supplements the General Catalogs of Wilson (1953) andEvans (1978) with published observations up to December, 1980. Onlyobservations with adequate spectral resolution and standardized to theIAU or Wilson velocity systems are included in the catalog. The accuracyand sources of the data, and the weighting system used in constructingthe catalog are discussed. A sample section of the catalog is presentedand explained.
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The early F-type stars - Refined classification, confrontation with Stromgren photometry, and the effects of rotation
The classification for early F-type stars in the MK spectralclassification system presented by Gray and Garrison (1987) is refined.The effect of rotation on spectral classification and ubvy-betaphotometry of early F-type stars is examined. It is found that theclassical luminosity criterion, the 4417 A/4481 A ratio givesinconsistent results. It is shown that most of the stars in the DeltaDelphini class of metallic-line stars are either normal or areindistinguishable from proto-Am stars. It is suggested that thedesignation Delta Delphini should be dropped. The classifications arecompared with Stromgren photometry. The effects of rotation on thedelta-c1 index in the early-F field dwarfs is demonstrated.
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Young, high-velocity stars. I - Rotational velocities and a catalog of early-type stars at the South Galactic Pole
A catalog has been compiled of 305 early-type stars to F0 and 15thmagnitude in 218 sq deg at the South Galactic Pole. Stromgren photometryand medium- and high-resolution spectra for many of the catalog starshave been obtained. Radial velocities, H-beta line widths, Balmer jumps,and Ca II K line equivalent widths have been measured and tabulated.Rotational velocities were obtained for eight distant A stars and arefound to be typical of values for normal young main sequence stars.
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Young, high-velocity a stars. II - Misidentified, ejected, or unique?
The ages, abundances, and kinematics of a large number of early-typestars at the south Galactic pole are derived to examine the properties,augment the sample of high-velocity stars, and study hypothesesconcerning their origin. The results are compared to a group of normal Astars near the disk. It is suggested that at around 6.5 X 10 to the 8thyr ago, a major source of relatively low abundance hydrogen was accretedby the Galactic disk, forming young high-velocity stars that do notpartake of the age-abundance-kinematics relationships shown by otherstellar groupings.
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Catalogue of the energy distribution data in spectra of stars in the uniform spectrophotometric system.
Not Available
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Interstellar reddening towards the south galactic pole
B, A and F type stars are observed in an area of about 400 squaredegrees around the galactic south pole (SGP) using theStroemgren-Crawford uvby-beta system at the 60 cm telescope of theBochum station on La Silla, Chile. With calibrations for B and F typestars and the provisional calibration for the stars of Stroemgren's LateGroup-A-stars, intrinsic (b-y)0 colors are derived and then used todescribe the interstellar absorption structure of the SGP. To determinethe galactic extinction perpendicular to the galactic plane, thereddening values of distant stars are averaged in order to include boththe reddened and unreddened areas at the SGP. A mean value E(b-y)SGPequals 0.019 m is derived and is found to agree well with earliervalues, except with that of Knude (1977). Explanations for the deviationare considered, implying that Knude's value is systematically too high.
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Radial Velocities and Spectral Classification of A-Type Stars Near the South Galactic Pole
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971PASP...83..643B&db_key=AST
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A finding list of early-type stars near the south galactic pole.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971AJ.....76..338S&db_key=AST
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Line strengths for southern OB stars-II. Observations with moderate dispersion
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969MNRAS.144...31B&db_key=AST
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A Finding List of Stars of Spectral Type A7 and Earlier in Regions at High Galactic Latitudes. II. South Galactic Pole
An objective prism survey of stars of spectral type A7 and earlier hasbeen made of stars in a 230 square degree region at the South GalacticPole as part of an investigation of galactic structure perpendicular tothe galactic plane. The survev reported here was made with the 4°prism on the Tonantzintla Schmidt telescope and the UV prism on theMichigan Curtis Schmidt telescope at Cerro Tololo. A finding listcontaining positions and spectral types for 180 stars is presented, withfinding charts for the stars too faint to be included in the CD or BDcatalogues.
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Three-colour photometry of early-type stars near the galactic poles
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963MNRAS.127...83W&db_key=AST
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Radial velocities of bright southern stars, III
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963MNRAS.126...29B&db_key=AST
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INHABITED SKY
