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Metallicities and activities of southern stars
Aims. We present the results from high-resolution spectroscopicmeasurements to determine metallicities and activities of bright starsin the southern hemisphere. Methods: We measured the iron abundances([Fe/H]'s) and chromospheric emission indices (log h{R}'{HK})of 353 solar-type stars with V = 7.5-9.5. [Fe/H] abundances aredetermined using a custom χ2 fitting procedure within alarge grid of Kurucz model atmospheres. The chromospheric activitieswere determined by measuring the amount of emission in the cores of thestrong Caii HK lines. Results: Our comparison of the metallicity sampleto other [Fe/H] determinations was found to agree at the ±0.05dex level for spectroscopic values and at the ±0.1 dex level forphotometric values. The distribution of chromospheric activities isdescribed by a bimodal distribution, agreeing with the conclusions fromother works. Also an analysis of Maunder minimum status was attempted,and it was found that 6 ± 4 stars in the sample could be in aMaunder minimum phase of their evolution and hence the Sun should onlyspend a few per cent of its main sequence lifetime in Maunder minimum.Based on observations made with the ESO telescopes at the La SillaParanal observatory under programme ID's 076.C-0578(B) and077.C-0192(A). Table 4 is only available in electronic form at the CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/485/571
| Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
| The reality of old moving groups - the case of HR 1614. Age, metallicity, and a new extended sample
We prove the existence of the old and metal-rich moving group HR 1614.This is done using the new Hipparcos parallaxes in combination withmetallicities derived from Strömgren photometry, supported bydynamical simulations of the evolution of old moving groups in thegalactic potential. A new selection criterion for this moving group ispresented as well as a new, extended sample of probable member stars. Inparticular we find that the HR 1614 moving group has an age of about 2Gyr (using Bertelli et al. 1994 isochrones) and a [Fe/H] =~ 0.19 +/-0.06 dex. We also revisit and apply our new selection criterion to thesamples in Eggen (1992) and Eggen (1998b). It is found that, whenbinaries and stars with too low metallicity have been removed, 15 of hisstars fulfill our criteria. Based on observations with the ESA Hipparcossatellite.
| 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.
| Stroemgren photometry of F- and G-type stars brighter than V = 9.6. I. UVBY photometry
Within the framework of a large photometric observing program, designedto investigate the Galaxy's structure and evolution, Hβ photometryis being made for about 9000 stars. As a by-product, supplementary uvbyphotometry has been made. The results are presented in a cataloguecontaining 6924 uvby observations of 6190 stars, all south ofδ=+38deg. The overall internal rms errors of one observation(transformed to the standard system) of a program star in the interval6.5
| Photometry of the comet Halley : solar analogs selected along the path (November 1985 - Mat 1986)
Not Available
| Fundamental data for southern stars (Second List)
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1959MNRAS.119..638E&db_key=AST
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Membro dei seguenti gruppi:
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Osservazione e dati astrometrici
| Costellazione: | Regolo |
| Ascensione retta: | 16h10m17.45s |
| Declinazione: | -47°54'51.4" |
| Magnitudine apparente: | 8.955 |
| Distanza: | 103.842 parsec |
| Moto proprio RA: | -97.6 |
| Moto proprio Dec: | -88.9 |
| B-T magnitude: | 9.757 |
| V-T magnitude: | 9.022 |
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