Bibcode
Santos, N. C.; Israelian, G.; García López, R. J.; Mayor, M.; Rebolo, R.; Randich, S.; Ecuvillon, A.; Domínguez Cerdeña, C.
Referencia bibliográfica
Astronomy and Astrophysics, v.427, p.1085-1096 (2004)
Fecha de publicación:
12
2004
Revista
Número de citas
47
Número de citas referidas
41
Descripción
In this paper we present beryllium (Be) abundances in a large sample of
41 extra-solar planet host stars, and for 29 stars without any known
planetary-mass companion, spanning a large range of effective
temperatures. The Be abundances were derived through spectral synthesis
done in standard Local Thermodynamic Equilibrium, using spectra obtained
with various instruments. The results seem to confirm that overall,
planet-host stars have ``normal'' Be abundances, although a small, but
not significant, difference might be present. This result is discussed,
and we show that this difference is probably not due to any stellar
``pollution'' events. In other words, our results support the idea that
the high-metal content of planet-host stars has, overall, a
``primordial'' origin. However, we also find a small subset of
planet-host late-F and early-G dwarfs that might have higher than
average Be abundances. The reason for the offset is not clear, and might
be related either to the engulfment of planetary material, to galactic
chemical evolution effects, or to stellar-mass differences for stars of
similar temperature.
Based on observations collected with the VLT/UT2 Kueyen telescope
(Paranal Observatory, ESO, Chile) using the UVES spectrograph (Observing
runs 66.C-0116 A, 66.D-0284 A, and 68.C-0058 A), and with the William
Herschel and Nordic Optical Telescopes, operated on the island of La
Palma by the Isaac Newton Group and jointly by Denmark, Finland,
Iceland, and Norway, respectively, in the Spanish Observatorio del Roque
de los Muchachos of the Instituto de Astrofísica de Canarias.