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@PhDThesis{Souza:2015:LoLaSc,
               author = "Souza, Vitor Moura Cardoso e Silva",
                title = "Location of large scale reconnection at Earth's dayside 
                         magnetopause as probed by analytical X-line models and in situ 
                         observations",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2015",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2015-02-24",
             keywords = "reconex{\~a}o magn{\'e}tica, magnetopausa diurna, magnetosfera 
                         terrestre, magnetic reconnection, dayside magnetopause, Earth's 
                         magnetosphere.",
             abstract = "The magnetic reconnection process is believed to occur throughout 
                         the Universe whenever distinct magnetized plasma regimes come 
                         together and interact. It has also been shown to be the dominant 
                         process for the solar wind-magnetosphere interaction. In this work 
                         the large scale aspect of the magnetic field reconnection process 
                         is investigated: where does reconnection occur along the 
                         Earth\${'}\$s dayside magnetopause and what are the key 
                         parameters governing its location? We perform an intercomparison 
                         of three analytical model\${'}\$s, which predict the 
                         reconnection X-line location and orientation, namely Trattner et 
                         al. (2007), Gonzalez and Mozer (1974), and Swisdak and Drake 
                         (2007) against two sets of reconnection events which are 
                         identified mostly by the in situ detection of accelerated plasma 
                         flows. In the first set, we show four fortuitous, 
                         quasi-simultaneous dayside magnetopause crossing events where two 
                         widely separated spacecraft detect reconnection signatures, and 
                         the possible X-line location can be inferred from the 
                         observations. The X-line models are then used and their 
                         predictions are compared with the expected X-line location 
                         obtained from observation. The results suggest that an extended (> 
                         5 Earth radii in length), component-type reconnection X-line may 
                         in fact be a likely scenario at Earth\${'}\$s dayside 
                         magnetopause, connecting and structuring the reconnection 
                         characteristics on far apart observation points. In the second set 
                         of reconnection events, we have analyzed the X-line models 
                         performance in predicting the observed reconnection outflow 
                         direction, i.e., its north-south and/or east-west senses, in a 
                         total of 116 single magnetopause crossing events where 
                         reconnection-generated plasma flows were clearly present. We found 
                         that the Swisdak and Drake (2007)s X-line model had a slightly 
                         better performance in predicting both accelerated plasma flow 
                         components: north-south (72\% of the cases) and east-west (54\% 
                         of the cases), as compared to the Trattner et al. (2007) model 
                         (66\% north-south, 37\% east-west), and Gonzalez and Mozer 
                         (1974) model (60\% north-south, 42\% east-west). The Swisdak and 
                         Drake (2007) model takes into account the realistic asymmetrical 
                         magnetic fields and plasma density conditions across the 
                         magnetopause boundary layer, thus the result suggests that in 
                         addition to external boundary conditions such as the 
                         interplanetary magnetic field orientation and solar wind dynamic 
                         pressure value, the local plasma and magnetic field conditions 
                         play an important role in determining the large scale X-line 
                         orientation at Earth\${'}\$s dayside magnetopause, in particular 
                         the local plasma \$\beta\$, as it has been shown elsewhere 
                         (PHAN et al., 2013). RESUMO: Acredita-se que o processo de 
                         reconex{\~a}o magn{\'e}tica seja capaz de ocorrer por todo o 
                         Universo toda vez que plasmas magnetizados distintos interajam. 
                         Tem-se tamb{\'e}m mostrado que a reconex{\~a}o magn{\'e}tica 
                         {\'e} o processo dominante na intera{\c{c}}{\~a}o vento 
                         solar-magnetosfera terrestre. Neste trabalho, o aspecto de larga 
                         escala do processo de reconex{\~a}o magn{\'e}tica {\'e} 
                         investigado. Em particular, busca-se identificar em qual(is) 
                         regi{\~a}o({\~o}es) ao longo da magnetopausa diurna terrestre a 
                         reconex{\~a}o magn{\'e}tica ocorre, e ainda quais os 
                         par{\^a}metros-chave que ditam o modo como a linha X deve 
                         localizar-se. Utilizando dois conjuntos de eventos de 
                         reconex{\~a}o magn{\'e}tica, os quais s{\~a}o identificados 
                         principalmente pela detec{\c{c}}{\~a}o de fluxos de plasma 
                         acelerados, faz-se uma compara{\c{c}}{\~a}o entre tr{\^e}s 
                         modelos anal{\'{\i}}ticos: Trattner et al. (2007), Gonzalez and 
                         Mozer (1974), and Swisdak and Drake (2007), que predizem a 
                         localiza{\c{c}}{\~a}o e orienta{\c{c}}{\~a}o da linha X de 
                         reconex{\~a}o. No primeiro conjunto de eventos, mostram-se quatro 
                         eventos fortuitos de cruzamentos quasi-simult{\^a}neos da 
                         magnetopausa diurna terrestre nos quais dois sat{\'e}lites 
                         amplamente espa{\c{c}}ados detectam assinaturas de 
                         reconex{\~a}o, e como a localiza{\c{c}}{\~a}o da prov{\'a}vel 
                         linha X pode ser inferida atrav{\'e}s das 
                         observa{\c{c}}{\~o}es. Os modelos de linha X s{\~a}o ent{\~a}o 
                         utilizados e suas respectivas predi{\c{c}}{\~o}es comparadas com 
                         a localiza{\c{c}}{\~a}o esperada da linha X. Os resultados 
                         sugerem que uma extensa (> 5 raios terrestres em comprimento) 
                         linha X de reconex{\~a}o por componente pode de fato constituir 
                         um cen{\'a}rio prov{\'a}vel na magnetopausa diurna terrestre. 
                         Tal linha conectaria e estruturaria as assinaturas de 
                         reconex{\~a}o detectadas em pontos substancialmente distantes. No 
                         segundo conjunto de eventos de reconex{\~a}o, analizou-se a 
                         performance dos modelos de linha X em prever a 
                         dire{\c{c}}{\~a}o, isto {\'e}, sentidos norte-sul e/ou 
                         leste-oeste, dos plasmas acelerados em 116 eventos de cruzamentos 
                         simples (somente um sat{\'e}lite) pela magnetopause diurna 
                         terrestre para os quais os fluxos de plasma provenientes do 
                         processo de reconex{\~a}o estivessem claramente presentes. 
                         Encontrou-se que o modelo de linha X de Swisdak and Drake (2007) 
                         obteve uma performance ligeiramente melhor na predi{\c{c}}{\~a}o 
                         de ambas as componentes dos plasmas acelerados: norte-sul (72\% 
                         dos casos) e leste-oeste (54\% dos casos), quando comparado com o 
                         modelo de Trattner et al. (2007) (66\% norte-sul, 37\% 
                         leste-oeste), e o modelo de Gonzalez and Mozer (1974) (60\% 
                         norte-sul, 42\% leste-oeste). O modelo de Swisdak and Drake 
                         (2007) leva em considera{\c{c}}{\~a}o condi{\c{c}}{\~o}es 
                         real{\'{\i}}sticas de assimetrias nos campos magn{\'e}ticos e 
                         densidades do plasma atrav{\'e}s da magnetopausa, portanto o 
                         resultado acima sugere que al{\'e}m de condi{\c{c}}{\~o}es de 
                         contorno externas, tais como a orienta{\c{c}}{\~a}o do campo 
                         magn{\'e}tico interplanet{\'a}rio e o valor da press{\~a}o 
                         din{\^a}mica do vento solar, as condi{\c{c}}{\~o}es locais de 
                         campo magn{\'e}tico e plasma, em particular o par{\^a}metro 
                         \$\beta\$, possuem papel fundamental na 
                         determina{\c{c}}{\~a}o da orienta{\c{c}}{\~a}o da linha X de 
                         larga escala na magnetopausa diurna terrestre, como tem sido 
                         mostrado na literatura (PHAN et al., 2013).",
            committee = "Dal Lago, Alisson (presidente) and Koga, Daiki (orientador) and 
                         Mendes Junior, Odim (orientador) and Dallaqua, Renato S{\'e}rgio 
                         and Sibeck, David Gary and Cardoso, Fl{\'a}via Reis",
           copyholder = "SID/SCD",
         englishtitle = "An{\'a}lise da localiza{\c{c}}{\~a}o da reconex{\~a}o 
                         magn{\'e}tica em larga escala na magnetopausa diurna terrestre 
                         por meio de modelos anal{\'{\i}}ticos de linha X e 
                         observa{\c{c}}{\~o}es in situ",
             language = "en",
                pages = "212",
                  ibi = "8JMKD3MGP3W34P/3J3GFGP",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3J3GFGP",
           targetfile = "publicacao.pdf",
        urlaccessdate = "05 dez. 2020"
}


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