ABUNDANCES OF STARS WITH PLANETS: TRENDS WITH CONDENSATION TEMPERATURE ,

Journal Article · Sun May 01 04:00:00 EDT 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/732/1/55· OSTI ID:21574629

Schuler, Simon C; Cunha, Katia; Smith, Verne V ^[1]; Flateau, Davin ^[2]; King, Jeremy R ^[3]; Ghezzi, Luan ^[4]

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1. National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States)
2. Department of Physics, University of Cincinnati, Cincinnati, OH 45221 (United States)
3. Department of Physics and Astronomy, Clemson University, 118 Kinard Laboratory, Clemson, SC 29634 (United States)
4. Observatorio Nacional, Rua General Jose Cristino, 77, 20921-400 Sao Cristovao, Rio de Janeiro, RJ (Brazil)

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 {approx}< 0.05 dex. The stars in our sample have all been previously shown to have abundances that correlate with the condensation temperature (T{sub c}) of the elements in the sense of increasing abundances with increasing T{sub c}; 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 T{sub c}, although slopes of linear least-square fits to the [m/H]-T{sub c} relations for all but two stars are smaller here than in previous studies. When considering the refractory elements (T{sub c} >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.

• OSTI ID: 21574629
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 732; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ABUNDANCE
DIMENSIONLESS NUMBERS
ELEMENT ABUNDANCE
EVOLUTION
GALACTIC EVOLUTION
PLANETS
SIGNAL-TO-NOISE RATIO
SPECTROSCOPY
STARS