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@MastersThesis{Silva:2002:CoQuEv,
               author = "Silva, Ronaldo Oliveira da",
                title = "Composi{\c{c}}{\~a}o qu{\'{\i}}mica, evolu{\c{c}}{\~a}o e 
                         cinem{\'a}tica de estrelas do tipo solar",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2002",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2002-12-11",
             keywords = "estrelas, tipo solar, composi{\c{c}}{\~a}o qu{\'{\i}}mica, Via 
                         L{\'a}ctea, evolu{\c{c}}{\~a}o qu{\'{\i}}mica, an{\'a}lise 
                         espectrosc{\'o}pica, s{\'{\i}}ntese espectral, stars, solar 
                         type, chemical, composition, Milky Way Galaxy, chemical evolution, 
                         spectroscopic analysis, synthesis.",
             abstract = "A composi{\c{c}}{\~a}o qu{\'{\i}}mica das estrelas de tipo 
                         solar {\'e} um diagn{\'o}stico extremamente valioso da 
                         evolu{\c{c}}{\~a}o qu{\'{\i}}mica do disco da Gal{\'a}xia. 
                         Existe alguma evid{\^e}ncia de que tal evolu{\c{c}}{\~a}o tem 
                         sido heterog{\^e}nea no espa{\c{c}}o e ao longo do tempo e que a 
                         composi{\c{c}}{\~a}o qu{\'{\i}}mica do Sol pode n{\~a}o ser 
                         um padr{\~a}o representativo de abund{\^a}ncias. Neste trabalho, 
                         foram obtidas as abund{\^a}ncias dos elementos qu{\'{\i}}micos 
                         C, N, Na, Mg, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, 
                         Y, Zr, Ba, La, Ce, Nd e Sm em uma amostra de estrelas de tipo 
                         solar na vizinhan{\c{c}}a solar (dist{\^a}ncia  25 pc). A 
                         t{\'e}cnica empregada foi a an{\'a}lise espectrosc{\'o}pica 
                         diferencial em rela{\c{c}}{\~a}o ao Sol, baseando-se em dados de 
                         alta resolu{\c{c}}{\~a}o (R ~ 46.000) e alta raz{\~a}o 
                         sinal/ru{\'{\i}}do (S/R > 300), obtidos com o espectr{\'o}grafo 
                         {\'e}chelle de bancada do telesc{\'o}pio de 1,5 m do CTIO. 
                         Adicionalmente, abund{\^a}ncias de C e N foram obtidas 
                         atrav{\'e}s de s{\'{\i}}ntese de bandas moleculares dos 
                         Sistemas Eletr{\^o}nicos Swan do C2 e Vermelho do CN 
                         utilizando-se um programa de s{\'{\i}}ntese espectral. Os 
                         par{\^a}metros atmosf{\'e}ricos foram estabelecidos usando cores 
                         fotom{\'e}tricas, o equil{\'{\i}}brio de excita{\c{c}}{\~a}o 
                         e ioniza{\c{c}}{\~a}o de linhas do Fe e a an{\'a}lise da 
                         temperatura e da luminosidade estelares no diagrama HR. Os 
                         resultados de abund{\^a}ncias qu{\'{\i}}micas aqui obtidos 
                         proporcionam uma melhor compreens{\~a}o da rela{\c{c}}{\~a}o 
                         das abund{\^a}ncias conhecidas para o Sol com a das estrelas 
                         an{\~a}s de tipo G da popula{\c{c}}{\~a}o local, uma vez que as 
                         raz{\~o}es de abund{\^a}ncias de diversos elementos (em 
                         rela{\c{c}}{\~a}o ao ferro) obtidas para estrelas de 
                         metalicidade semelhante {\`a} solar diferem daquelas obtidas para 
                         o Sol. Tais resultados tamb{\'e}m contribuem para um melhor 
                         entendimento do processo de evolu{\c{c}}{\~a}o qu{\'{\i}}mica 
                         da vizinhan{\c{c}}a solar e do enriquecimento 
                         nucleossint{\'e}tico do disco gal{\'a}ctico. ABSTRACT: The 
                         chemical composition of the long-lived solar-type stars is an 
                         extremely valuable diagnostic of the chemical evolution of the 
                         Galactic disc. There is some evidence that such evolution has been 
                         heterogeneous both in time and space, and that the Sun might not 
                         be a typical star in what concerns its abundance pattern. In this 
                         work, we have determined the abundances of the elements C, N, Na, 
                         Mg, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, 
                         La, Ce, Nd and Sm, in a sample of solar-type stars in the solar 
                         neighborhood (distance  25 pc). The technique was the 
                         differential spectroscopic analysis, relative to the Sun, based on 
                         high resolution (R ~ 46,000) and high sign-to-noise ratio (S/N > 
                         300) data obtained with the bench-mounted {\'e}chelle 
                         spectrograph of the 1.5 m telescope of CTIO. In addition, 
                         abundances of C and N were obtained based on molecular bands of 
                         the Swan and Red Electronic Systems using a spectral synthesis 
                         code. The atmospheric parameters were established using 
                         photometric colors, the excitation and ionization equilibria of 
                         the Fe lines and the analysis of the stellar temperature and 
                         luminosity in the HR diagram. The results of chemical abundances 
                         obtained here contribute to a better understanding of the relation 
                         of the abundances known for the Sun with that of the local 
                         population of G-type dwarf stars, since the abundances of many 
                         elements (relative to iron) obtained for solar metalicity stars 
                         are different from that of the Sun. Such results also contribute 
                         to a better understanding of the chemical evolution in the solar 
                         neighborhood and of the nucleosynthetic enrichment of the galactic 
                         disk.",
            committee = "Jablonski, Francisco Jos{\'e} (presidente) and Milone, Andr{\'e} 
                         de Castro (orientador) and Mello, Gustavo Frederico Porto de 
                         (orientador) and Barbuy, Beatriz Leonor Silveira and Souza, Bruno 
                         Vaz Castilho de",
           copyholder = "SID/SCD",
         englishtitle = "Chemical composition, evolution and cinematic of solar-type 
                         stars.",
             language = "pt",
                pages = "129",
                  ibi = "6qtX3pFwXQZ3P8SECKy/zdaoi",
                  url = "http://urlib.net/rep/6qtX3pFwXQZ3P8SECKy/zdaoi",
           targetfile = "publicacao.pdf",
        urlaccessdate = "2019, Dec. 14"
}


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