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arXiv · 0805.3936

Spectroscopic metallicities of Vega-like stars

Abstract

Aims: To determine the metallicities of 113 Southern Hemisphere Vega-like candidate stars in relation to the Exoplanet host group and field stars. Methods: We applied two spectroscopic methods of abundance determinations: equivalent width measurements together with the ATLAS9 (Kurucz 1993) model atmospheres and the WIDTH9 program, and a comparison of observed spectra with the grid of synthetic spectra of Munari et al. (2005). Results: For the Vega-like group, the metallicities are indistinguishable from those of field stars not known to be associated with planets or disks. This result is quite different from the metallicities of Exoplanet host stars which are metal-rich in comparison to field stars.

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C. Saffe, M. Gomez, O. Pintado, E. Gonzalez. 2008-05-26. Spectroscopic metallicities of Vega-like stars. https://doi.org/10.1051/0004-6361%3A200810260

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