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arXiv · astro-ph/0109245

Photospheric Abundances of Volatile and Refractory Elements in Planet-Harboring Stars

Y. Takeda·B. Sato·E. Kambe·W. Aoki·S. Honda·S. Kawanomoto·S. Masuda·H. Izumiura·E. Watanabe·H. Koyano·H. Maehara·Y. Norimoto·T. Okada·Y. Shimizu·F. Uraguchi·K. Yanagisawa·M. Yoshida·S. Miyama·H. Ando
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Abstract

By using the high-dispersion spectra of 14 bright planet-harboring stars (along with 4 reference stars) observed with the new coude echelle spectrograph at Okayama Astrophysical Observatory, we investigated the abundances of volatile elements (C, N, O, S, Zn; low condensation temperature Tc) in order to examine whether these show any significant difference compared to the abundances of other refractory elements (Si, Ti, V, Fe, Co, Ni; high Tc) which are known to be generally overabundant in those stars with planets, since a Tc-dependence is expected if the cause of such a metal-richness is due to the accretion of solid planetesimals onto the host star. We found, however, that all elements we studied behave themselves quite similarly to Fe (i.e., [X/Fe]~0) even for the case of volatile elements, which may suggest that the enhanced metallicity in those planet-bearing stars is not so much an acquired character (by accretion of rocky material) as rather primordial.

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Y. Takeda, B. Sato, E. Kambe, W. Aoki, S. Honda, S. Kawanomoto, S. Masuda, H. Izumiura, E. Watanabe, H. Koyano, H. Maehara, Y. Norimoto, T. Okada, Y. Shimizu, F. Uraguchi, K. Yanagisawa, M. Yoshida, S. Miyama, H. Ando. 2001-09-16. Photospheric Abundances of Volatile and Refractory Elements in Planet-Harboring Stars. https://doi.org/10.1093/pasj%2F53.6.1211

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