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arXiv · astro-ph/0202456

Beryllium abundances in stars hosting giant planets

Abstract

We have derived beryllium abundances in a wide sample of stars hosting planets, with spectral types in the range F7V-K0V, aimed at studying in detail the effects of the presence of planets on the structure and evolution of the associated stars. Predictions from current models are compared with the derived abundances and suggestions are provided to explain the observed inconsistencies. We show that while still not clear, the results suggest that theoretical models may have to be revised for stars with Teff<5500K. On the other hand, a comparison between planet host and non-planet host stars shows no clear difference between both populations. Although preliminary, this result favors a ``primordial'' origin for the metallicity ``excess'' observed for the planetary host stars. Under this assumption, i.e. that there would be no differences between stars with and without giant planets, the light element depletion pattern of our sample of stars may also be used to further investigate and constraint Li and Be depletion mechanisms.

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N. C. Santos, R. J. Garcia Lopez, G. Israelian, M. Mayor, R. Rebolo, A. Garcia-Gil, M. R. Perez de Taoro, S. Randich. 2002-02-25. Beryllium abundances in stars hosting giant planets. https://doi.org/10.1051/0004-6361%3A20020280

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