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@PhDThesis{Silva:2017:SoInFl,
               author = "Silva, Suzana de Souza e Almeida",
                title = "On the influence of nonlocal heat flux on energy transport and 
                         balance in the solar atmosphere. (Sobre a influ{\^e}ncia do fluxo 
                         de calor n{\~a}o local sobre o transporte e balan{\c{c}}o de 
                         energia na atmosfera solar)",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2017",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2017-01-24",
             keywords = "solar corona, heat flux, heat transfer, plasma heating, 
                         magnetohydrodynamics, simulation, coroa solar, fluxo de calor, 
                         transfer{\^e}ncia de calor, aquecimento do plasma, 
                         magnetohidrodin{\^a}mica, simula{\c{c}}{\~a}o.",
             abstract = "In the solar corona, heat flux is one of the key processes of 
                         energy transport. Since the coronal plasma can be described as 
                         weakly collisional, classical formulation for the heat flux might 
                         no longer be the most accurate description. In a medium with fewer 
                         collisions, the heat flux will have contributions not only from 
                         neighboring particles, but also from particles coming from other 
                         regions along the magnetic field line. Hence, a better description 
                         of the heat flux in this context might be offered by a nonlocal 
                         formulation. We have implemented a non local heat flux in a 3D MHD 
                         model and we investigated its effects on the thermal evolution of 
                         the system. We simulate the evolution of plasma and magnetic field 
                         using this model and considering two different formulations for 
                         heat flux: classical (local) and nonlocal one. The initial 
                         magnetic field was obtained from a potential extrapolation of the 
                         observed line-ofsight component of photospheric magnetic field for 
                         AR11226. We evolved the system by imposing a field velocity at the 
                         bottom of the simulation box which shifted footpoints of the 
                         magnetic field lines. Then we compared the differences in the 
                         evolution of plasma obtained using the two different formulations 
                         for the heat flux. The inclusion of a nonlocal formulation for 
                         heat flux leads to considerable differences in the average 
                         temperature profile of the lower atmosphere and transition region 
                         compared to classical formulation. There are also remarkable 
                         differences concerning the contributions from energy transport and 
                         from source terms to the temperature depending on the formulation 
                         used. Our results suggest that a different heat flux formulation 
                         affects considerably the heating dynamics and temperature 
                         evolution of the plasma. RESUMO: Na coroa solar, o fluxo de calor 
                         {\'e} um dos principais processos de transporte de energia. Uma 
                         vez que o plasma coronal pode ser descrito como fracamente 
                         colisional, a formula{\c{c}}{\~a}o cl{\'a}ssica para o fluxo de 
                         calor pode n{\~a}o ser a descri{\c{c}}{\~a}o mais precisa. Em 
                         um meio com menos colis{\~o}es, o fluxo de calor ter{\'a} 
                         contribui{\c{c}}{\~o}es n{\~a}o apenas de part{\'{\i}}culas 
                         vizinhas, mas tamb{\'e}m de part{\'{\i}}culas provenientes de 
                         outras regi{\~o}es ao longo da linha de campo magn{\'e}tico. 
                         Assim, uma melhor descri{\c{c}}{\~a}o do fluxo de calor neste 
                         contexto pode ser oferecida por uma formula{\c{c}}{\~a}o 
                         n{\~a}o-local. Implementamos um fluxo de calor n{\~a}o-local em 
                         um modelo 3D MHD e investigamos seus efeitos na 
                         evolu{\c{c}}{\~a}o t{\'e}rmica do sistema. N{\'o}s simulamos a 
                         evolu{\c{c}}{\~a}o do plasma e campo magn{\'e}tico usando esse 
                         modelo considerando as seguintes formula{\c{c}}{\~o}es para o 
                         fluxo de calor: cl{\'a}ssico (local) e n{\~a}o-local. O campo 
                         magn{\'e}tico inicial foi obtido a partir de uma 
                         extrapola{\c{c}}{\~a}o potencial da componente observada da 
                         linha de visada do campo magn{\'e}tico fotosf{\'e}rico para 
                         AR11226. N{\'o}s evolu{\'{\i}}mos o sistema impondo 
                         deslocamento dos footpoints das linhas de campo magn{\'e}tico. Ao 
                         final, comparamos as diferen{\c{c}}as na evolu{\c{c}}{\~a}o do 
                         plasma obtido utilizando as distintas formula{\c{c}}{\~o}es para 
                         o fluxo de calor. A inclus{\~a}o de uma formula{\c{c}}{\~a}o 
                         n{\~a}o-local para o fluxo de calor conduz a diferen{\c{c}}as 
                         consider{\'a}veis no perfil de temperatura m{\'e}dia da 
                         atmosfera inferior e da regi{\~a}o de transi{\c{c}}{\~a}o em 
                         compara{\c{c}}{\~a}o com a formula{\c{c}}{\~a}o cl{\'a}ssica. 
                         H{\'a} tamb{\'e}m diferen{\c{c}}as not{\'a}veis quanto {\`a}s 
                         contribui{\c{c}}{\~o}es do transporte de energia e dos termos de 
                         origem para a temperatura dependendo da formula{\c{c}}{\~a}o 
                         utilizada. Nossos resultados sugerem que uma 
                         formula{\c{c}}{\~a}o de fluxo de calor diferente afeta 
                         consideravelmente a din{\^a}mica de aquecimento e a 
                         evolu{\c{c}}{\~a}o da temperatura do plasma.",
            committee = "Batista, Inez Staciarini (presidente) and Alves, Maria 
                         Virg{\'{\i}}nia (orientadora) and Santos, Jean Carlo 
                         (orientador) and B{\"u}chner, J{\"o}rg Artur Erick (orientador) 
                         and Vieira, Luis Eduardo Antunes and Caldas, Iber{\^e} Luis and 
                         Pereira, Vera Jatenco Silva",
           copyholder = "SID/SCD",
         englishtitle = "Sobre a influ{\^e}ncia do fluxo de calor n{\~a}o-local sobre o 
                         transporte e balan{\c{c}}o de energia na atmosfera solar",
             language = "en",
                pages = "103",
                  ibi = "8JMKD3MGP3W34P/3N3M6F8",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3N3M6F8",
           targetfile = "publicacao.pdf",
        urlaccessdate = "30 nov. 2020"
}


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