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Accurate abundance patterns of solar twins and analogs. Does the anomalous solar chemical composition come from planet formation?
We derive the abundance of 19 elements in a sample of 64 stars withfundamental parameters very similar to solar, which minimizes the impactof systematic errors in our spectroscopic 1D-LTE differential analysis,using high-resolution (R?60 000), high signal-to-noise ratio(S/N?200) spectra. The estimated errors in the elemental abundancesrelative to solar are as small as ?0.025 dex. The abundance ratios[X/Fe] as a function of [Fe/H] agree closely with previously establishedpatterns of Galactic thin-disk chemical evolution. Interestingly, themajority of our stars show a significant correlation between [X/Fe] andcondensation temperature (T_C). In the sample of 22 stars withparameters closest to solar, we find that, on average, low TCelements are depleted with respect to high TC elements in thesolar twins relative to the Sun by about 0.08 dex (?20%). Anincreasing trend is observed for the abundances as a function ofTC for 900
| 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.
| Catalogue of proper motions in the declination of stars of the Moscow zenith zone.
Not Available
| UBV Photometry of Stars whose Positions are Accurately Known
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984A&AS...57..357O&db_key=AST
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Membre dels grups següents:
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Dades d'Observació i Astrometria
| Constel·lació: | Ursa Major |
| Ascensió Recta: | 10h39m05.86s |
| Declinació: | +55°30'45.0" |
| Magnitud Aparent: | 8.614 |
| Distancia: | 55.525 parsecs |
| Moviment propi RA: | 34.7 |
| Moviment propi Dec: | -35.4 |
| B-T magnitude: | 9.418 |
| V-T magnitude: | 8.681 |
Catàlegs i designacions:
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