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@MastersThesis{DiazRamirez:2018:OrLiAl,
               author = "Diaz Ramirez, Yaherlyn Elimar",
                title = "Origem das linhas de alta ioniza{\c{c}}{\~a}o em n{\'u}cleos 
                         ativos de Gal{\'a}xias",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2018",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2018-02-26",
             keywords = "n{\'u}cleos gal{\'a}ticos ativos, linhas de alta 
                         ioniza{\c{c}}{\~a}o, linhas coronais, fotoioniza{\c{c}}{\~a}o, 
                         infravermelho: galaxias, active galaxy nuclei, high ionization 
                         lines, coronal lines, fotoionization, infrared: galaxy.",
             abstract = "N{\'u}cleos ativos de gal{\'a}xia (AGNs) apresentam em seus 
                         espectros linhas proibidas de alta ioniza{\c{c}}{\~a}o ou linhas 
                         coronais (CLs). Devido {\`a} energia necess{\'a}ria para sua 
                         produ{\c{c}}{\~a}o (> 100 eV), as CLs tra{\c{c}}am uma parte 
                         importante do cont{\'{\i}}nuo ionizante que nem sempre {\'e} 
                         diretamente acess{\'{\i}}vel a partir de observa{\c{c}}{\~o}es 
                         devido {\`a} absor{\c{c}}{\~a}o Gal{\'a}ctica e interna. 
                         Sabe-se que as CLs s{\~a}o geralmente emitidas em regi{\~o}es 
                         compactas pr{\'o}ximas {\`a} fonte central, mas as 
                         condi{\c{c}}{\~o}es f{\'{\i}}sicas do g{\'a}s e os mecanismos 
                         associados a sua produ{\c{c}}{\~a}o ainda est{\~a}o em debate. 
                         Neste trabalho analisamos os parsecs mais internos de uma amostra 
                         de 4 gal{\'a}xias ativas pr{\'o}ximas com emiss{\~a}o coronal 
                         proeminente para estudar os mecanismos f{\'{\i}}sicos 
                         respons{\'a}veis pela produ{\c{c}}{\~a}o das CLs. Com este 
                         intuito, observa{\c{c}}{\~o}es de alta resolu{\c{c}}{\~a}o 
                         angular ( 0.1/px) coletadas com espectr{\'o}grafos de campo 
                         integral e {\'o}ptica adaptativa permitem estudar a 
                         distribui{\c{c}}{\~a}o espacial do g{\'a}s de alta 
                         ioniza{\c{c}}{\~a}o assim como modelar as raz{\~o}es [Si vi]/Br 
                         , [S ix]/Pa, [Ca viii]/Br e [Si vii]/Br usando o c{\'o}digo de 
                         fotoioniza{\c{c}}{\~a}o CLOUDY. Encontramos que a emiss{\~a}o 
                         coronal nos objetos estudados {\'e} estendida, at{\'e} 
                         dist{\^a}ncias da ordem de 150-200 pc. O g{\'a}s distribui-se 
                         preferencialmente ao longo do jato r{\'a}dio em cada uma das 
                         gal{\'a}xias. A distribui{\c{c}}{\~a}o do g{\'a}s {\'e} 
                         altamente inhomog{\^e}nea, com m{\'u}ltiplos knots em 
                         emiss{\~a}o. Mapas de canais mostram que a emiss{\~a}o coronal 
                         {\'e} turbulenta, com velocidades de dispers{\~a}o acima dos 900 
                         km s\−1. Modelos de fotoioniza{\c{c}}{\~a}o realizados 
                         com CLOUDY comprovam que a fotoioniza{\c{c}}{\~a}o n{\~a}o 
                         {\'e} o {\'u}nico mecanismo f{\'{\i}}sico respons{\'a}vel 
                         pela emiss{\~a}o das linhas coronais. Processos energ{\'e}ticos 
                         tais como choques s{\~a}o necess{\'a}rios para explicar a 
                         emiss{\~a}o do g{\'a}s de alta ioniza{\c{c}}{\~a}o. De modo 
                         geral, o nosso trabalho demonstra a utilidade de 
                         observa{\c{c}}{\~o}es IFUs de alta resolu{\c{c}}{\~a}o angular 
                         para entender, de forma mais acurada, os processos 
                         f{\'{\i}}sicos nos parsecs mais internos dos AGNs. ABSTRACT: 
                         Active galactic nuclei (AGNs) present, in their spectra, lines of 
                         high ionization or coronal lines (CLs). Due to the potential 
                         necessary for its production (> 100 eV), the CLs trace a part of 
                         the ionizing continuum which is not always directly accessible 
                         from observations due to Galactic and internal absorption. It is 
                         known that CLs are generally emitted in compact regions near the 
                         central source, but the physical conditions of the gas and the 
                         mechanisms associated with their productio are under discussion. 
                         In this work we analyze the most internal parsecs of a sample of 4 
                         nearby active galaxies with prominent coronal emission to study 
                         the physical mechanisms responsible for the production of CLs. For 
                         this purpose, observations of high angular resolution ( 0.1/px) 
                         collected with integral field spectroscopy and adaptive optics 
                         allowed the study of the spatial distribution of the high 
                         ionization gas and model the emission line flux ratios [Si vi]/Br 
                         , [S ix]/Pa, [Ca viii]/Br and [Si vii]/Br using CLOUDY. We find 
                         that the coronal emission in the studied objects is extended to 
                         distances of up to 150-200 pc. The gas is distributed along the 
                         radio jet in each of the galaxies. The gas distribution is highly 
                         inhomogeneous, with multiple knots in emission. Channel maps show 
                         that coronal emission is turbulent, with high velocity dispersion, 
                         reaching values of 900 km s\−1. Photoionization models of 
                         CLOUDY show that photoionization is not the only physical 
                         mechanism responsible for the emission of coronal lines. Another 
                         processes such as shocks are necessary to explain the emission of 
                         the high ionization gas. Overall, our work highlights the need of 
                         high angular IFU observations to understand, more accurately, the 
                         physical processes associated to the central few parsecs in 
                         AGNs.",
            committee = "Rodrigues, Cl{\'a}udia Vilega (presidente) and Ardila, Alberto 
                         Rodriguez (orientador) and Braga, Jo{\~a}o and Krabbe, Angela 
                         Cristina",
         englishtitle = "Origin of high ionization lines in active galactic nuclei",
             language = "pt",
                pages = "127",
                  ibi = "8JMKD3MGP3W34P/3QH9P4L",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3QH9P4L",
           targetfile = "publicacao real.pdf",
        urlaccessdate = "04 dez. 2020"
}


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