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@MastersThesis{Carlos:2015:AnQuDi,
               author = "Carlos, Mar{\'{\i}}lia Gabriela Cardoso Corr{\^e}a",
                title = "An{\'a}lise qu{\'{\i}}mica diferencial detalhada de estrelas de 
                         tipo solar pobres em metais com e sem planetas",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2015",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2015-04-14",
             keywords = "estrelas, estrelas abund{\^a}ncias, an{\'a}lise 
                         espectrosc{\'o}pica, planetas extrassolares, gal{\'a}xia disco, 
                         stars, stars abundances, spectroscopic analysis, extrasolar 
                         planets, galaxy disk.",
             abstract = "Este projeto {\'e} focado no estudo de estrelas de tipo solar 
                         moderadamente pobres em metais, com e sem planetas, para a 
                         investiga{\c{c}}{\~a}o da exist{\^e}ncia (ou n{\~a}o) de uma 
                         conex{\~a}o entre anomalias na composi{\c{c}}{\~a}o 
                         qu{\'{\i}}mica e a presen{\c{c}}a de planetas. Analisou-se 
                         espectros de alta resolu{\c{c}}{\~a}o e raz{\~a}o 
                         sinal-ru{\'{\i}}do (R=65.000, > 300, espectrografo MIKE, 
                         telesc{\'o}pio Magellan, Las Campanas Observatory, Chile) a fim 
                         de se derivar diferen{\c{c}}as de abund{\^a}ncias com 
                         alt{\'{\i}}ssima precis{\~a}o para elementos vol{\'a}teis e 
                         refrat{\'a}rios (erros entre 0,01 e 0,05 dex). A metodologia 
                         {\'e} baseada na an{\'a}lise espectrosc{\'o}pica diferencial, 
                         que tamb{\'e}m fornece diferen{\c{c}}as precisas em temperatura 
                         efetiva (\$T_{ef}\$), gravidade superficial (log g) e 
                         metalicidade ([Fe/H]) para diversos pares de estrelas parecidas em 
                         temperatura e metalicidade. Distinguimos estrelas do disco fino 
                         daquelas do disco espesso e as dividimos em grupos 
                         {"}homog{\^e}neos{"} em Tef e [Fe/H]. Para se obter as 
                         diferen{\c{c}}as em Tef, log g e [X/H] aplicamos o m{\'e}todo de 
                         largura equivalente aplicado a linhas do FeI e FeII com o 
                         aux{\'{\i}}lio do pacote IRAF e o c{\'o}digo MOOG, que resolve 
                         o transporte radiativo fotosf{\'e}rico considerando 
                         equil{\'{\i}}brio termodin{\^a}mico local. No caso do carbono a 
                         regi{\~a}o molecular \$C_{2}\$(0,0)\$\lambda\$5165A foi 
                         analisada por meio de s{\'{\i}}ntese espectral (via MOOG 
                         tamb{\'e}m). O nitrog{\^e}nio teve sua abund{\^a}ncia 
                         qu{\'{\i}}mica calculada via s{\'{\i}}ntese espectral das 
                         linhas 3882,52 A e 3882,70 A da banda (0,0) do sistema B-X Violeta 
                         do CN. Tamb{\'e}m verificou-se se h{\'a} alguma 
                         rela{\c{c}}{\~a}o entre as abund{\^a}ncias elementais 
                         diferenciais e suas temperaturas de condensa{\c{c}}{\~a}o de 
                         poeira por entre pares de estrelas similares. Foram estudadas 23 
                         estrelas, com resultados obtidos para 17 pares de estrelas. Quatro 
                         pares apresentaram resultados promissores que sugerem a 
                         defici{\^e}ncia de elementos refrat{\'a}rios em 
                         rela{\c{c}}{\~a}o a elementos vol{\'a}teis nas camadas mais 
                         externas das estrelas. Tr{\^e}s pares tiveram seus resultados 
                         descartados devido {\`a} incompatibilidade de par{\^a}metros 
                         fotosf{\'e}ricos entre as estrelas da an{\'a}lise diferencial e 
                         os outros pares devem ter a an{\'a}lise revista. ABSTRACT: The 
                         present project aims to study moderately metal-poor solar-type 
                         stars, with and without planets, to investigate the existence (or 
                         not) of a connection between abnormalities in the chemical 
                         composition of stars and the presence of planets. We analysed high 
                         resolution spectra with high signal to noise ratio (R = 65.000, S/ 
                         N > 300, MIKE spectrograph, Magellan Telescope, Las Campanas 
                         Observatory, Chile) in order to derive high precision abundance 
                         differences in volatile and refractory elements, with errors 
                         between 0,01 and 0,05 dex. The methodology is based on 
                         differential spectroscopic analysis, which also provides precise 
                         differences in temperature (\$T_{teff}\$) ,surface gravity (log 
                         g) and metallicity ([Fe/H]), for several pairs of stars similar in 
                         temperature and metallicity, The stars were distinguished in those 
                         which belongs to the thin or thick disk, and then divided into 
                         \${{"}}\$homogeneous\${{"}}\$ groups of \$T_{teff}\$ and 
                         [Fe/H]. In order to obtain the differences in \$T_{teff}\$, log 
                         g and [X/H] we applied the equivalent width method with the IRAF 
                         package and the MOOG code, which solves the photospheric radiative 
                         transfer assuming local thermodynamic equilibrium. In the case of 
                         carbon the molecular region \$C_{2}\$(0,0)\$\lambda\$5165A 
                         was analysed through spectral synthesis (via MOOG). For the 
                         nitrogen, we analysed the lines 3882,52 A and 3882,70 A in the 
                         molecular region of the violet CN B-X system through spectral 
                         synthesis as well. We als o verified whether there is any relation 
                         between the differential elemental abundances and the dust 
                         condensation temperatures among pairs of similar stars. In total, 
                         23 stars have been studied with results to 17 pairs of them. 
                         Amongst all these pairs, 4 showed promising results which 
                         confirmed the refractory elemental depletion in the external 
                         layers of stars. The result of three pairs are dis-carded since 
                         the derived photospheric parameters have no compatibility with 
                         their groups, the others pairs should be analysed again.",
            committee = "Rodrigues, Cl{\'a}udia Vilega (presidente) and Milone, Andr{\'e} 
                         de Castro (orientador) and Moreno, Jorge Luis Melendez 
                         (orientador) and Valio, Adriana Benetti Marques and Rossi, Silvia 
                         Cristina Fernandes",
           copyholder = "SID/SCD",
         englishtitle = "Detailed diferential chemical analisys of sun-like metal poor 
                         stars with or without planets",
             language = "pt",
                pages = "120",
                  ibi = "8JMKD3MGP3W34P/3J7RUPS",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3J7RUPS",
           targetfile = "publicacao.pdf",
        urlaccessdate = "29 nov. 2020"
}


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