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Spectroscopic metallicities for planet-host stars: extending the samples

N. C. Santos·G. Israelian·M. Mayor·J. P. Bento·P. C. Almeida·S. G. Sousa·A. Ecuvillon
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Abstract

We present stellar parameters and metallicities for 29 planet-host stars, as well as for a large volume-limited sample of 53 stars not known to be orbited by any planetary-mass companion. These stars add to the results presented in our previous series of papers, providing two large and uniform samples of 119 planet-hosts and 94 ``single'' stars with accurate stellar parameters and [Fe/H] estimates. The analysis of the results further confirms that stars with planets are metal-rich when compared with average field dwarfs. Important biases that may compromise future studies are also discussed. Finally, we compare the metallicity distributions for single planet-hosts and planet-hosts in multiple stellar systems. The results show that a small difference cannot be excluded, in the sense that the latter sample is slighly overmetallic. However, more data are needed to confirm this correlation.

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N. C. Santos, G. Israelian, M. Mayor, J. P. Bento, P. C. Almeida, S. G. Sousa, A. Ecuvillon. 2005-04-19. Spectroscopic metallicities for planet-host stars: extending the samples. https://doi.org/10.1051/0004-6361%3A20052895

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