Contenidos
Imágenes
Subir su imagen
DSS Images Other Images
Artículos relacionados
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.
| Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
| Classification of Population II Stars in the Vilnius Photometric System. II. Results
The results of photometric classification of 848 true and suspectedPopulation II stars, some of which were found to belong to Population I,are presented. The stars were classified using a new calibrationdescribed in Paper I (Bartkevicius & Lazauskaite 1996). We combinethese results with our results from Paper I and discuss in greaterdetail the following groups of stars: UU Herculis-type stars and otherhigh-galactic-latitude supergiants, field red horizontal-branch stars,metal-deficient visual binaries, metal-deficient subgiants, stars fromthe Catalogue of Metal-deficient F--M Stars Classified Photometrically(MDPH; Bartkevicius 1993) and stars from one of the HIPPARCOS programs(Bartkevicius 1994a). It is confirmed that high galactic latitudesupergiants from the Bartaya (1979) catalog are giants or even dwarfs.Some stars, identified by Rose (1985) and Tautvaisiene (1996a) as fieldRHB stars, appear to be ordinary giants according to our classification.Some of the visual binaries studied can be considered as physical pairs.Quite a large fraction of stars from the MDPH catalog are found to havesolar metallicity. A number of new possible UU Herculis-type stars, RHBstars and metal-deficient subgiants are identified.
| The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle
The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.
| 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.
| A photometric and spectroscopic search for luminous high latitude stars
Formulas, derived by Arellano Ferro and Mendoza in Paper I (1993), tocalculate Mv, log g, and (Fe/H) were applied to a group of 73A, F, and G stars of high galactic latitude previously classified assupergiant stars. The only star that showed, from data on hand, to beluminous, slightly iron deficient, and out of the galactic plane was BLTelescopii. The remainder of the sample either present controversialresults or are definitively giant or dwarf stars misclassified assupergiants. Thus, if luminous, young stars indeed exist out of thegalactic plane, they are extremely rare.
| Classification of Population II supergiants and related stars in the Vilnius system
The results of photometric classification in the Vilnius system of 117Population II supergiants, suspected supergiants, and related stars aregiven. Their photometric spectral types, intrinsic color indices (Y-V)0,color excesses E(Y-V), metallicities Fe/H, and absolute magnitudes MVare determined. It is shown that the system allows us to detect the UUHerculis-type supergiants photometrically. The analyzed SRd star samplefalls into two groups of metallicity and luminosity. Our photometricclassification assigns luminosity classes from III to V to 37 F-K starswith /b/ greater than 16 deg classified by Bartaya (1979) from objectiveprism spectra as supergiants.
| UBV photometry of stars whose positions are accurately known. III
UBV photometric observations of 417 stars at BD declination 35-49 degfrom the NPZT(74) catalog of Yasuda et al. (1982) and the AGK3R catalogof Corben (1978), obtained with the 40-cm Cassegrain reflector atKvistaberg Observatory during 1984-1985, are reported. The data arepresented in tables, and the mean errors per observation are given as0.016 mag in V, 0.011 mag in B-V, 0.012 mag in U-B for U less than 10,and 0.026 mag in U-B for U greater than 10.
| The UU Her-type stars - Possible tracers of recent star formation at high galactic latitudes
A general review of the group of UU Her-type stars proposed recently asa possible new type of variables is given. The available observations(spectra and photometry) reveal them as luminous Population I F-typesupergiants of normal composition. This fact contradicts their greatdistances above the galactic plane. As there is no reason so far todistrust the results from the spectroscopic analyses and photometry, thegalactic plane should be excluded as a possible birthplace of the UUHer-stars. In this respect they might probably indicate that recent starformation (though occasional) from already enriched material waspossible at high galactic latitudes. Moreover, normal Main-SequenceB-stars seem now also to be found there. Much attention is paid to thespecific semiregular variability of the UU Her-stars. The type ofpulsations remains conjectural, but simple radial pulsations shouldobviously be ruled out.
| Variable F-Type Supergiants Far above the Galactic Plane
Not Available
| Catalog of Indidual Radial Velocities, 0h-12h, Measured by Astronomers of the Mount Wilson Observatory
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJS...19..387A&db_key=AST
| A Finding List of Early-Type Stars in Regions of Intermediate Galactic Latitude
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969ApJ...157..327U&db_key=AST
|
Enviar un nuevo artículo
Enlaces relacionados
- - No se han encontrado enlaces -
En viar un nuevo enlace
Miembro de los siguientes grupos:
|
Datos observacionales y astrométricos
| Constelación: | Lince |
| Ascensión Recta: | 08h45m02.61s |
| Declinación: | +44°11'03.9" |
| Magnitud Aparente: | 8.839 |
| Distancia: | 178.891 parsecs |
| Movimiento Propio en Ascensión Recta: | -28.4 |
| Movimiento Propio en Declinación: | -30.8 |
| B-T magnitude: | 9.232 |
| V-T magnitude: | 8.872 |
Catálogos y designaciones:
|
