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@PhDThesis{CondeCuellar:2017:3DMoMa,
               author = "Conde Cuellar, Sandra Milena",
                title = "3D model magneto-acoustic waves in coronal loops observed during 
                         transient events",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2017",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2017-05-25",
             keywords = "flares, waves, magnetohydrodynamic, relation to magnetic field, 
                         structures, flares, ondas, magnetohidrodin{\^a}mica, 
                         rela{\c{c}}{\~a}o com o campo magn{\'e}tico, estruturas.",
             abstract = "We present a three-dimensional analysis of magneto-acoustic waves, 
                         along the seven coronal loops, observed on the active region NOAA 
                         11272 during the class B and C flares. We found 19-, 9-, 5-, 2-, 
                         1-, and 0.6-minute waves using the pixelised wavelet filtering 
                         method over images obtained from the Atmospheric Imaging Assembly 
                         instrument. We modelled the velocity of these waves along the 
                         extrapolated magnetic field lines that reproduce the observed 
                         loops in extreme ultraviolet. The extrapolation was made over 
                         magnetograms, got from the Helioseismic and Magnetic Imager 
                         instrument, using the linear force-free approximation. From our 
                         model, we found temperatures 10\$^{3}\$ (maior equivalente) T 
                         (menor equivalente) 1.8 x 10\$^{7}\$ K and densities 
                         10\$^{7}\$ (maior equivalente) n (menor equivalente) 
                         10\$^{17}\$ cm\$^{\−3}\$, covering from photosphere to 
                         corona, as expected in the solar atmosphere. Hence, we obtained 
                         acoustic c\$_{s}\$ \$\approx\$ 10\$^{2}\$ km 
                         s\$^{\−1}\$ and Alfv{\'e}nic \$\upsilon\$\$_{A}\$ 
                         \$\approx\$ 10\$^{4}\$ km s\$^{\−1}\$ velocities 
                         values which are in agreement with the literature. In addition, 
                         the brightness asymmetry observed along the coronal loops is 
                         explained by the magnetic field and Alfv{\'e}n velocity 
                         distributions along the extrapolated field lines. We found fast 
                         magneto-acoustic waves at the beginning of B3.8 and C1.9 flares 
                         and slow modes along the loops during all flares. Our 3D model 
                         represents an unprecedented method to study waves in coronal 
                         loops. All results are coherent with expected values in the solar 
                         atmosphere conditions. RESUMO: Apresentamos uma an{\'a}lise 
                         tridimensional de ondas magnetoac{\'u}sticas ao longo de sete 
                         loops coronais, observados na regi{\~a}o ativa NOAA 11272 durante 
                         os flares de classe B e C. Encontramos ondas de 19, 9, 5, 2, 1 e 
                         0.6 minutos usando o m{\'e}todo Pixelised Wavelet Filtering sobre 
                         imagens obtidas com o instrumento Atmospheric Imaging Assembly. 
                         Modelamos as velocidades dessas ondas ao longo das linhas de campo 
                         magn{\'e}tico extrapoladas que reproduzem os loops observados em 
                         ultravioleta extremo. A extrapola{\c{c}}{\~a}o foi feita sobre 
                         os magnetogramas obtidos com o instrumento Helioseismic and 
                         Magnetic Imager, usando a aproxima{\c{c}}{\~a}o Linear 
                         Force-Free. A partir do nosso modelo, encontramos temperaturas de 
                         10\$^{3}\$ (maior equivalente) T (menor equivalente) 1.8 x 
                         10\$^{7}\$ K e densidades de 10\$^{7}\$ (maior equivalente) n 
                         (menor equivalente) 10\$^{17}\$ cm\$^{\−3}\$, cobrindo 
                         desde a fotosfera at{\'e} a coroa, como esperado na atmosfera 
                         solar. Desta forma, obtivemos valores para as velocidades 
                         ac{\'u}stica e Alfv{\'e}nica de c\$_{s}\$ \$\approx\$ 
                         10\$^{2}\$ km s\$^{\−1}\$ e \$\upsilon\$\$_{A}\$ 
                         \$\approx\$ 10\$^{4}\$ km s\$^{\−1}\$ 
                         respectivamente, as quais est{\~a}o acorde com a literatura. 
                         Adicionalmente, a assimetria no brilho observada ao longo dos 
                         loops coronais {\'e} explicada pelas distribui{\c{c}}{\~o}es do 
                         campo magn{\'e}tico e da velocidade Alfv{\'e}n ao longo das 
                         linhas extrapoladas. N{\'o}s encontramos ondas 
                         magnetoac{\'u}sticas r{\'a}pidas no inicio dos flares B3.8 e 
                         C1.9 e modos lentos ao longo dos loops durante todos os flares. O 
                         nosso modelo representa um m{\'e}todo in{\'e}dito para estudar 
                         ondas em loops coronais. Todos os resultados s{\~a}o coerentes 
                         com os valores esperados nas condi{\c{c}}{\~o}es da atmosfera 
                         solar.",
            committee = "Costa, C{\'e}sar Augusto (presidente) and Costa, Joaquim Eduardo 
                         Rezende (orientador) and Viera, Luis Eduardo Antunes and Alves, 
                         Maria Virg{\'{\i}}nia and Castro, Carlos Guillermo Gim{\'e}nez 
                         de and Pereira, Vera Jatenco Silva and Silva Pereira, Vera 
                         Jatenco",
         englishtitle = "Modelo tridimensional de ondas magnetoac{\'u}sticas em ''loops'' 
                         coronais observados durante eventos transientes",
             language = "en",
                pages = "150",
                  ibi = "8JMKD3MGP3W34P/3NR6PP2",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3NR6PP2",
           targetfile = "publicacao.pdf",
        urlaccessdate = "27 nov. 2020"
}


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