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@MastersThesis{Botelho:2017:CaNiAn,
               author = "Botelho, Rafael Bueno",
                title = "Carbono e nitrog{\^e}nio em an{\~a}s de tipo solar com e sem 
                         planetas",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2017",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2017-03-02",
             keywords = "estrela do tipo solar, abund{\^a}ncia, espectroscopia 
                         {\'o}ptica, s{\'{\i}}ntese espectral estelar, exoplanetas, 
                         solar type star, abundance, optical spectroscopy, spectral stellar 
                         synthesis, exoplanets.",
             abstract = "Neste trabalho apresentamos os resultados da an{\'a}lise de 
                         espectros estelares no intuito de derivarmos a abund{\^a}ncia 
                         fotosf{\'e}rica do carbono (C) e nitrog{\^e}nio (N) para 
                         estrelas an{\~a}s do tipo solar, com e sem planetas j{\'a} 
                         detectados. Existem trabalhos que mostram que C e N (dois 
                         elementos vol{\'a}teis) s{\~a}o mais abundantes em estrelas com 
                         planetas, bem como h{\'a} trabalhos que afirmam que estrelas com 
                         planetas s{\~a}o deficientes em elementos refrat{\'a}rios com 
                         rela{\c{c}}{\~a}o aos vol{\'a}teis. C e N s{\~a}o elementos 
                         vol{\'a}teis, cuja abund{\^a}ncias devem ser comparadas com as 
                         abund{\^a}ncias de elementos refrat{\'a}rios a fim de verificar 
                         a contribui{\c{c}}{\~a}o da forma{\c{c}}{\~a}o planet{\'a}ria 
                         na composi{\c{c}}{\~a}o da estrela hospedeira. Analisando 
                         transi{\c{c}}{\~o}es moleculares na faixa de 3300\$\AA\$ a 
                         5300\$\AA\$ derivamos a abund{\^a}ncia do C e N para duas 
                         amostras de estrelas distintas: (i) parte da amostra de Y. Takeda 
                         (espectros coletados no Observat{\'o}rio Okayama, com 
                         resolu{\c{c}}{\~a}o R=70.000 e raz{\~a}o sinal-ru{\'{\i}}do 
                         S/N > 320) e (ii) 4 pares de estrelas similares de M. Carlos 
                         (espectros coletados no telesc{\'o}pio Magellan, Las Campanas 
                         Observatory, R=65.000 e S/N > 300). Os espectros da amostra de Y. 
                         Takeda precisaram ter o fluxo normalizado, estando j{\'a} 
                         reduzidos. Os espectros da amostra de M. Carlos j{\'a} se 
                         encontravam com fluxo normalizado. Empregando o c{\'o}digo de 
                         s{\'{\i}}ntese espectral MOOG, que resolve o transporte 
                         radiativo numa fotosfera estelar sob a hip{\'o}tese de 
                         equil{\'{\i}}brio termodin{\^a}mico local, definimos um 
                         conjunto de linhas moleculares como bons indicadores das 
                         abund{\^a}ncia do C e N, tendo medido tais abund{\^a}ncias 
                         elementais com erros bastante aceit{\'a}veis para o 
                         prop{\'o}sito deste estudo. As linhas espectrais s{\~a}o dos 
                         sistemas eletr{\^o}nicos A-X do CH, D-A do C2, B-X do CN e A-X do 
                         NH (este {\'u}ltimo apenas empregado para an{\'a}lise 
                         espectrosc{\'o}pica da amostra de M. Carlos). Encontramos numa 
                         das estrelas de um par de estrelas similares da amostra de M. 
                         Carlos, a princ{\'{\i}}pio ambas sem planetas, que mostra 
                         defici{\^e}ncia de elementos refrat{\'a}rios com 
                         rela{\c{c}}{\~a}o aos vol{\'a}teis, sugerindo que ela deva 
                         possuir planeta(s), terrestre ou gasoso e a outra n{\~a}o. 
                         Notamos tamb{\'e}m que estrelas an{\'a}logas solares do disco 
                         fino com planetas gasosos s{\~a}o ligeiramente mais abundantes em 
                         C e N como ocorre para o Fe. ABSTRACT: In this work we present the 
                         results of stellar spectral analysis in order to derive the 
                         photospheric abundance of carbon (C) and nitrogen (N) for solar 
                         type dwarf stars, with and without already detected planets. There 
                         are works that show that C and N (two volatile elements) are more 
                         abundant in stars with planets, as well as works which affirm that 
                         stars with planets are deficient in refractory elements with 
                         respect to volatiles. C and N are volatile elements whose 
                         abundances must be compared with the abundances of refractory 
                         elements in order to verify the contribution of the planetary 
                         formation in the composition of the host star. Analyzing molecular 
                         transitions in the range of 3300\$\AA\$ to 5300\$\AA\$ we 
                         derive abundance of C and N for two distinct star samples: (i) 
                         part of the Y. Takeda sample (Spectra collected at the Okayama 
                         Observatory, with a resolution of R = 70,000 and signal-to-noise 
                         ratio S/N>320) and (ii) 4 pairs of similar stars of M. Carlos 
                         (spectra collected in the Magellan telescope, Las Campanas 
                         Observatory, R = 65,000 and S/N>300). The spectra of the Y. Takeda 
                         sample had to have the normalized flow already reduced. The 
                         spectra of the sample of M. Carlos were already with normalized 
                         flux. Using the MOOG spectral synthesis code, which solves the 
                         radiative transport in a stellar photosphere under the hypothesis 
                         of local thermodynamic equilibrium, we defined a set of molecular 
                         lines as good indicators of the abundance of C and N, having 
                         measured such elemental abundances with errors quite acceptable 
                         for the purpose of this study. The spectral lines are from the 
                         electron systems of CH A-X, C2 D-A, CN B-X and NH A-X (the latter 
                         only used for spectroscopic analysis of the M. Carlos sample). We 
                         found in one of the stars of a pair of similar stars of the sample 
                         of M. Carlos, at first both without planets, that shows deficiency 
                         of refractory elements with respect to the volatile ones, 
                         suggesting that it must own planet(s), terrestrial or gaseous and 
                         the other do not. We also note that thin disk solar-analog stras 
                         with gaseous planets are slightly more abundant in C and N as is 
                         the case for Fe.",
            committee = "Jablonski, Francisco Jos{\'e} (presidente) and Milone, Andr{\'e} 
                         de Castro (orientador) and Braga, Jo{\~a}o and Rossi, Silvia 
                         Cristina Fernandes",
           copyholder = "SID/SCD",
         englishtitle = "Carbon and nitrogen in solar type dwarfs with and without 
                         planets",
             language = "pt",
                pages = "122",
                  ibi = "8JMKD3MGP3W34P/3NCMP98",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3NCMP98",
           targetfile = "publicacao.pdf",
        urlaccessdate = "30 nov. 2020"
}


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