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We present a high-precision chemical analysis of iota Horologii, a planet-host field star thought to have formed in the Hyades. Elements with atomic number 6<=Z<=30 have abundances that are in excellent agreement with those of the cluster within the +/-0.01 dex (or ~2%) precision errors. Heavier elements show a range of abundances such that about half of the Z>30 species analyzed are consistent with those of the Hyades, while the other half are marginally enhanced by 0.03+/-0.01 dex (~7+/-2%). The lithium abundance, A(Li), is very low compared to the well-defined A(Li)-Teff relation of the cluster. For its Teff, iota Horologiis lithium content is about half the Hyades. Attributing the enhanced lithium depletion to the planet would require a peculiar rotation rate, which we are unable to confirm. Our analysis of the stars chromospheric activity suggests Prot=5d, which is significantly shorter than previously reported. Models of Galactic orbits place iota Horologii hundreds of parsecs away from the Hyades cluster at formation. Thus, we find the claim of a shared birthplace very difficult to justify.
We show that the exoplanet-host star iota Horologii, alias HD17051, which belongs to the so-called Hyades stream, was formed within the primordial Hyades stellar cluster and has evaporated towards its present location, 40 pc away. This result has bee
We present a high-precision differential abundance analysis of 16 solar-type stars in the Hyades open cluster based on high resolution, high signal-to-noise ratio (S/N ~ 350 - 400) spectra obtained from the McDonald 2.7m telescope. We derived stellar
To detect stellar activity cycles and study the possible star-planet interactions (SPIs), we have developed both HK$alpha$ and SPI-HK$alpha$ projects since 1999 and 2012 respectively. In this work, we present preliminary results of possible SPIs st
We present the refinement of the crystal structure of charge-ordered LuFe2O4, based on single-crystal x-ray diffraction data. The arrangement of the different Fe-valence states, determined with bond-valence-sum analysis, corresponds to a stacking of
Time series of spectroscopic, speckle-interferometric, and optical long-baseline-interferometric observations confirm that $ u$ Gem is a hierarchical triple system. It consists of an inner binary composed of two B-type stars and an outer classical Be