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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 N2K Consortium. VII. Atmospheric Parameters of 1907 Metal-rich Stars: Finding Planet-Search Targets We report high-precision atmospheric parameters for 1907 stars in theN2K low-resolution spectroscopic survey, designed to identify metal-richFGK dwarfs likely to harbor detectable planets. Of these stars, 284 arein the ideal temperature range for planet searches,Teff<=6000 K, and have a 10% or greater probability ofhosting planets based on their metallicities. The stars in thelow-resolution spectroscopic survey should eventually yield >60 newplanets, including 8-9 hot Jupiters. Short-period planets have alreadybeen discovered orbiting the survey targets HIP 14810 and HD 149143.
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Takýmyýldýz: | Buyuk Ayi |
Sað Açýklýk: | 10h37m59.57s |
Yükselim: | +54°53'14.5" |
Görünürdeki Parlaklýk: | 9.183 |
özdevim Sað Açýklýk: | -81.8 |
özdevim Yükselim: | -67.5 |
B-T magnitude: | 9.992 |
V-T magnitude: | 9.25 |
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