Skip to main content
Article
Abundances of Stars with Planets: Trends with Condensation Temperature
The Astrophysical Journal
  • Simon C Schuler, National Optical Astronomy Observatory
  • Davin Flateau, University of Cincinnati
  • Katia Cunha, National Optical Astronomy Observatory
  • Jeremy R King, Clemson University
  • Luan Ghezzi, Observatorio Nacional, Rua General Jose Cristano
  • Verne V Smith, National Optical Astronomy Observatory
Document Type
Article
Publication Date
5-1-2011
Publisher
The American Astronomical Society
Abstract
Precise abundances of 18 elements have been derived for 10 stars known to host giant planets from high signal-to-noise ratio, high-resolution echelle spectroscopy. Internal uncertainties in the derived abundances are typically 0.05 dex. The stars in our sample have all been previously shown to have abundances that correlate with the condensation temperature (Tc) of the elements in the sense of increasing abundances with increasing Tc; these trends have been interpreted as evidence that the stars may have accreted H-depleted planetary material. Our newly derived abundances also correlate positively with Tc, although slopes of linear least-square fits to the [m/H]–Tc relations for all but two stars are smaller here than in previous studies. When considering the refractory elements (Tc > 900 K) only, which may be more sensitive to planet formation processes, the sample can be separated into a group with positive slopes (four stars) and a group with flat or negative slopes (six stars). The four stars with positive slopes have very close-in giant planets (three at 0.05 AU) and slopes that fall above the general Galactic chemical evolution trend. We suggest that these stars have accreted refractory-rich planet material but not to the extent that would increase significantly the overall stellar metallicity. The flat or negative slopes of the remaining six stars are consistent with recent suggestions of a planet formation signature, although we show that the trends may be the result of Galactic chemical evolution.
Comments

IOP Publishing holds the copyright to this article.

The published version can be found here: http://iopscience.iop.org/0004-637X/732/1/55

Citation Information
Please use publisher's recommended citation.