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The ROSAT all-sky survey catalogue of optically bright late-type giants and supergiants
We present X-ray data for all late-type (A, F, G, K, M) giants andsupergiants (luminosity classes I to III-IV) listed in the Bright StarCatalogue that have been detected in the ROSAT all-sky survey.Altogether, our catalogue contains 450 entries of X-ray emitting evolvedlate-type stars, which corresponds to an average detection rate of about11.7 percent. The selection of the sample stars, the data analysis, thecriteria for an accepted match between star and X-ray source, and thedetermination of X-ray fluxes are described. Catalogue only available atCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Improved Mean Positions and Proper Motions for the 995 FK4 Sup Stars not Included in the FK5 Extension
Not Available
| Metallicism among A and F giant stars
132 stars considered as A and F giants have been studied for theirproperties in the Geneva photometric system. It is shown that thissystem to derive the temperature, absolute magnitude and Fe/H value forstars in this part of the HR diagram. 36 percent of the stars of oursample exhibit an enhanced value Delta m2 that can be interpreted interms of Fe/H. The red limit of stars having an enhanced Fe/H value is0.225 in B2-V1 or 6500 K in Teff. This corresponds to the limit definedby Vauclair and Vauclair (1982) where the diffusion timescale is equalto the stellar lifetime and permits the assumption that the diffusion isthe process responsible for the metallicism observed in the A and Fgiants.
| The chemical evolution of the solar neighborhood. I - A bias-free reduction technique and data sample
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Osservazione e dati astrometrici
| Costellazione: | Camaleonte |
| Ascensione retta: | 11h18m34.30s |
| Declinazione: | -79°40'07.0" |
| Magnitudine apparente: | 6.35 |
| Distanza: | 64.516 parsec |
| Moto proprio RA: | 41.1 |
| Moto proprio Dec: | -29.7 |
| B-T magnitude: | 6.657 |
| V-T magnitude: | 6.384 |
Cataloghi e designazioni:
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