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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

HIGH PRECISION ABUNDANCES IN THE 16 Cyg BINARY SYSTEM: A SIGNATURE OF THE ROCKY CORE IN THE GIANT PLANET

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Autor(es):
Maia, Marcelo Tucci [1] ; Melendez, Jorge [1] ; Ramirez, Ivan [2, 3]
Número total de Autores: 3
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Dept Astron IAG, BR-05508900 Sao Paulo - Brazil
[2] Univ Texas Austin, Dept Astron, Austin, TX 78712 - USA
[3] Univ Texas Austin, McDonald Observ, Austin, TX 78712 - USA
Número total de Afiliações: 3
Tipo de documento: Artigo Científico
Fonte: Astrophysical Journal Letters; v. 790, n. 2 AUG 1 2014.
Citações Web of Science: 53
Resumo

We study the stars of the binary system 16 Cygni to determine with high precision their chemical composition. Knowing that the component B has a detected planet of at least 1.5 Jupiter masses, we investigate if there are chemical peculiarities that could be attributed to planet formation around this star. We perform a differential abundance analysis using high resolution (R = 81,000) and high S/N (similar to 700) CFHT/ESPaDOnS spectra of the 16 Cygni stars and the Sun; the latter was obtained from light reflected of asteroids. We determine differential abundances of the binary components relative to the Sun and between components A and B as well. We achieve a precision of sigma less than or similar to 0.005 dex and a total error similar to 0.01 dex for most elements. The effective temperatures and surface gravities found for 16 Cyg A and B are T-eff = 5830 +/- 7 K, log g = 4.30 +/- 0.02 dex, and T-eff = 5751 +/- 6K, log g = 4.35 +/- 0.02 dex, respectively. The component 16 Cyg A has ametallicity ({[}Fe/H]) higher by 0.047 +/- 0.005 dex than 16 Cyg B, as well as a microturbulence velocity higher by 0.08 km s(-1). All elements show abundance differences between the binary components, but while the volatile difference is about 0.03 dex, the refractories differ by more and show a trend with condensation temperature, which could be interpreted as the signature of the rocky accretion core of the giant planet 16 Cyg Bb. We estimate a mass of about 1.5-6 M-circle times for this rocky core, in good agreement with estimates of Jupiter's core. (AU)

Processo FAPESP: 12/24392-2 - Espectroscopia de alta precisão: impacto no estudo de planetas, estrelas, a galáxia e cosmologia
Beneficiário:Jorge Luis Melendez Moreno
Linha de fomento: Auxílio à Pesquisa - Temático