Proper motions of Hipparcos stars in two plate areas.
Not Available
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Determination of highly precise proper motions for 32 HIPPARCOS stars from photographic plates.
Not Available
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A uvbyβ photometric calibration of iron abundances in supergiant stars.
A photometric reddening-free calibration for [Fe/H] valid for giant andsupergiant stars of intermediate temperature, has been obtained usingthe Stroemgren uvbyβ system. Galactic supergiants, supergiants inthe Magellanic Clouds and Galactic metal deficient red giants withspectroscopic determinations of [Fe/H] were used as calibrators. Thecalibration can be used to predict [Fe/H] with an accuracy of 0.33 dex,valid for stars with 0.14<[m_1_]<0.70 in the iron abundance range-2.5<[Fe/H]<+0.3. This shows the potential of supergiant stars astracers of iron abundances in other galaxies. Evidence that Galacticluminous F-G stars are intrinsically bluer than their counterparts inthe Magellanic Clouds is offered.
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Photometry of F-K type bright giants and supergiants. I - Intermediate band and H-Beta observations
Over 1500 observations of 560 bright giants and supergiants of types F-Kare presented and compared to the observations by Gray and Olsen (1991).The present results include intermediate-band which is slightlydifferent from the Stromgren data by Gray and Olsen due to a differentwidth for the v filter. A systematic difference in m(1) - M(1) withdecreasing temperature is noted in the two H-Beta data sets, and thecorrelations are defined.
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Photometry of F-K type bright giant and supergiants. II - Calibration on indices in terms of luminosity reddening and abundance of F-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1991AJ....102.1826E&db_key=AST
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The calibration of the Stromgren photometric system for A, F and early G supergiants. I - The observational data
An empirical calibration of the Stromgren uvby-beta photometric systemfor the A, F, and early G supergiants is being derived. This paperexplains the observational program and the photometric reductiontechniques used and presents a catalog of new Stromgren photometry forover 600 A, F, and G supergiants.
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Supergiants and the Galactic metallicity gradient. II - Spectroscopic abundances for 64 distant F- to M-type supergiants
The metallicity gradient in the Galactic disk from in situ stars withvisual magnitude ranging from 6 to 10 is analyzed. Atmosphericparameters and detailed chemical abundances for 64 Population Isupergiants of spectral types F through M and luminosity classes Iathrough II have been determined. The derived Fe/H ratios ranging from-0.5 to + 0.7 show a mean value of +0.13 with an estimated uncertaintyof + or - 0.2. A subset of 25 supergiants fainter than 7th magnitudelying in the direction of the Galactic center shows a Fe/H mean of +0.18+ or - 0.04, while a similar sample of 15 faint supergiants lying in thedirection of the Galactic anticenter shows a lower Fe/H mean of +0.07 +or - 0.06. For a sample of bright supergiants analyzed by Luck andLambert (1985), the mean abundance pattern for all 64 stars showed thefollowing: deficient C and O along with enhancement of N, indicatingmixing of CNO-cycled material to the stellar surfaces; an apparent Srenhancement attributed to departures from LTE; and an essentially solarpattern of other chemical elements.
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Finding list and spectral classifications for southern luminous stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976AJ.....81..225M&db_key=AST
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INHABITED SKY
