Bibcode
Ecuvillon, A.; Israelian, G.; Santos, N. C.; Shchukina, N. G.; Mayor, M.; Rebolo, R.
Bibliographical reference
Astronomy and Astrophysics, Volume 445, Issue 2, January II 2006, pp.633-645
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1
2006
Journal
Citations
92
Refereed citations
74
Description
We present a detailed and uniform study of oxygen abundances in 155
solar type stars, 96 of which are planet hosts and 59 of which form part
of a volume-limited comparison sample with no known planets. EW
measurements were carried out for the [O I] 6300 Å line and the O
I triplet, and spectral synthesis was performed for several OH lines.
NLTE corrections were calculated and applied to the LTE abundance
results derived from the O I 7771-5 Å triplet. Abundances from [O
I], the O I triplet and near-UV OH were obtained in 103, 87 and 77
dwarfs, respectively. We present the first detailed and uniform
comparison of these three oxygen indicators in a large sample of
solar-type stars. There is good agreement between the [O/H] ratios from
forbidden and OH lines, while the NLTE triplet shows a systematically
lower abundance. We found that discrepancies between OH, [O I] and the O
I triplet do not exceed 0.2 dex in most cases. We have studied abundance
trends in planet host and comparison sample stars, and no obvious
anomalies related to the presence of planets have been detected. All
three indicators show that, on average, [O/Fe] decreases with [Fe/H] in
the metallicity range -0.8< [Fe/H] < 0.5. The planet host stars
present an average oxygen overabundance of 0.1-0.2 dex with respect to
the comparison sample.