@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/ibi/8JMKD3MGP3W34P/3PNL7CH",
targetfile = "publicacao.pdf",
urlaccessdate = "27 abr. 2024"
}