Beryllium abundances in stars with planets:Extending the sample

Abstract

Context: Chemical abundances of light elements as beryllium in planet-host stars allow us to study the planet formation scenarios and/or investigate possible surface pollution processes. Aims: We present here an extension of previous beryllium abundance studies. The complete sample consists of 70 stars hosting planets and 30 stars without known planetary companions. The aim of this paper is to further assess the trends found in previous studies with less number of objects. This will provide more information on the processes of depletion and mixing of light elements in the interior of late type stars, and will provide possible explanations for the abundance differences between stars that host planets and "single" stars. Methods: Using high resolution UVES spectra, we measure beryllium abundances of 26 stars that host planets and 1 "single" star mainly using the lambda 3131.065 A Be II line, by fitting synthetic spectra to the observational data. We also compile beryllium abundance measurements of 44 stars hosting planets and 29 "single" stars from the literature, resulting in a final sample of 100 objects. Results: We confirm that the beryllium content is roughly the same in stars hosting planets and in "single" stars at temperatures Teff > 5700K. The sample is still small for Teff < 5500K, but it seems that the scatter in Be abundances of dwarf stars is slightly higher at these cooler temperatures. Conclusions: We search for distinctive characteristics of planet hosts through correlations of Be abundance versus Li abundance, age, metallicity and oxygen abundance. These could provide some insight in the formation and evolution of planetary systems, but we did not find any clear correlation.

12 pages, 9 figures Accepted; A&A 2011

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Cited by in corpus (8)

• Metal-rich accretion and thermohaline instabilities in exoplanets-host stars: consequences on the light elements abundances
• Chemical abundances of 1111 FGK stars from the HARPS GTO planet search program IV. Carbon and C/O ratios for Galactic stellar populations and planet hosts
• Chemical abundances of 1111 FGK stars from the HARPS-GTO planet search sample. III. Sulfur
• Be abundances in cool main-sequence stars with exoplanets
• Implications of the spectroscopic abundances in α Centauri A and B
• Scenarios to explain extreme Be depletion in solar-like stars: accretion or rotation effects ?
• Angular momentum and lithium transport from main sequence to sub-giant and red giant low-mass stars
• Using Lithium and Beryllium to Study Structure and Evolution of Rotating Stars