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@MastersThesis{Mesquita:2018:DeVeTe,
               author = "Mesquita, Amanda L{\'u}cia",
                title = "Determina{\c{c}}{\~a}o de velocidades e tempos de chegada de 
                         eje{\c{c}}{\~o}es coronais de massa direcionadas para a Terra 
                         utilizando o m{\'e}todo CORSET",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2018",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2017-10-30",
             keywords = "eje{\c{c}}{\~o}es coronais de massa, CME halo, velocidade de 
                         expans{\~a}o lateral, tempo de chegada, CORSET, coronal mass 
                         ejections, halo CME, expansion speed, travel time, CORSET.",
             abstract = "Eje{\c{c}}{\~o}es coronais de massa, do ingl{\^e}s Coronal Mass 
                         Ejections (CMEs), s{\~a}o grandes estruturas 
                         constitu{\'{\i}}das de plasma e campo magn{\'e}tico que 
                         s{\~a}o expelidas pelo Sol na heliosfera. CMEs na 
                         dire{\c{c}}{\~a}o Sol-Terra, denominadas CMEs do tipo halo, 
                         s{\~a}o a principal causa de tempestades geomagn{\'e}ticas. 
                         Prever a chegada de CMEs na Terra {\'e} necess{\'a}rio para 
                         evitar danos ou falhas em sistemas tecnol{\'o}gicos amplamente 
                         utilizados, como as redes de transmiss{\~a}o de energia 
                         el{\'e}trica. Entretanto, a maneira como observamos as CMEs nos 
                         impede de fazer medidas diretas da velocidade de 
                         propaga{\c{c}}{\~a}o frontal, necess{\'a}ria para descrever 
                         cinematicamente esse fen{\^o}meno. Schwenn et al. (2001) e 
                         Schwenn et al. (2005) propuseram o uso da velocidade de 
                         expans{\~a}o lateral das CMEs como aproxima{\c{c}}{\~a}o para a 
                         velocidade radial de propaga{\c{c}}{\~a}o, obtendo bons 
                         resultados para predi{\c{c}}{\~a}o do tempo de viagem de CMEs na 
                         dire{\c{c}}{\~a}o da Terra. Neste trabalho, calculamos as 
                         velocidades de expans{\~a}o lateral para um conjunto de 36 
                         eventos utilizando um algoritmo computacional chamado CORonal 
                         SEgmatation Technique (CORSET), que rastreia a CME e calcula 
                         par{\^a}metros cinem{\'a}ticos, como as velocidades radial e de 
                         expans{\~a}o. Os tempos de chegada das CMEs foram obtidos com 
                         base em observa{\c{c}}{\~o}es de correspondentes 
                         interplanet{\'a}rios de CMEs nas vizinhan{\c{c}}as da Terra e 
                         comparados com os tempos calculados a partir de um modelo 
                         emp{\'{\i}}rico. A partir dos resultados dos 36 eventos 
                         obtivemos uma rela{\c{c}}{\~a}o emp{\'{\i}}rica para 
                         determinar tempos de chegada de CMEs, descrita pela express{\~a}o 
                         T\$_{tr}\$ = 174, 98 \− 16, 40  ln(V\$_{exp}\$), onde 
                         V\$_{exp}\$ {\'e} a velocidade de expans{\~a}o. ABSTRACT: 
                         Coronal Mass Ejections (CMEs) are large structures constituted of 
                         plasma and magnetic field that are expelled by the Sun into the 
                         heliosphere. CMEs pointing along the Sun-Earth line, called halo 
                         CMEs, are the main cause of geomagnetic storms. It is necessary to 
                         forecast the arrival of CMEs at Earth to avoid damages or failures 
                         in commonly used technological systems, such as power grids 
                         system. However, the way that we see the CMEs prevents us from 
                         making direct measurements of the frontal propagation speed 
                         necessary to kinematically describe this phenomenon. Schwenn et 
                         al. (2001) and Schwenn et al. (2005) proposed the use of the 
                         lateral expansion speed of the CMEs as a proxy to the radial 
                         speed. They obtained good results to predict the travel time of 
                         CMEs towards Earth. In this work, we calculate the expansion speed 
                         for a set of 36 events using a computational algorithm called 
                         CORonal SEgmatation Technique (CORSET), which tracks the CME and 
                         calculates kinematic parameters, such as radial and expansion 
                         speeds. The arrival times were obtained based on observations of 
                         interplanetary counterparts of CMEs in the vicinity of the Earth 
                         and compared to the arrival times calculated by using an empirical 
                         model. From the results of the 36 events we obtained an empirical 
                         model to determine arrival times of CMEs, described by the 
                         expression T\$_{tr}\$ = 174, 98 \− 16, 40  
                         ln(V\$_{exp}\$), where V\$_{exp}\$ is the expansion speed.",
            committee = "Wrasse, Cristiano Max (presidente) and Dal Lago, Alisson 
                         (orientador) and Braga, Carlos Roberto (orientador) and Costa, 
                         Joaquim Eduardo Rezende and Raulin, Jean Pierre",
         englishtitle = "Determination of coronal mass ejection velocity and travel time to 
                         earth using CORSET method",
             language = "pt",
                pages = "127",
                  ibi = "8JMKD3MGP3W34P/3PNL7CH",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3PNL7CH",
           targetfile = "publicacao.pdf",
        urlaccessdate = "29 nov. 2020"
}


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