Busca avançada
Ano de início
Entree
(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Predicting the Time of Arrival of Coronal Mass Ejections at Earth From Heliospheric Imaging Observations

Texto completo
Autor(es):
Braga, Carlos Roberto [1, 2] ; Vourlidas, Angelos [2] ; Stenborg, Guillermo [3] ; Dal Lago, Alisson [4] ; Souza de Mendonca, Rafael Rodrigues [4] ; Echer, Ezequiel [4]
Número total de Autores: 6
Afiliação do(s) autor(es):
[1] George Mason Univ, Fairfax, VA 22030 - USA
[2] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 - USA
[3] US Naval Res Lab, Space Sci Div, Washington, DC - USA
[4] Natl Inst Space Res, Sao Jose Dos Campos, SP - Brazil
Número total de Afiliações: 4
Tipo de documento: Artigo Científico
Fonte: JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS; v. 125, n. 9 SEP 2020.
Citações Web of Science: 0
Resumo

The time of arrival (ToA) of coronal mass ejections (CMEs) at Earth is a key parameter due to the space weather phenomena associated with the CME arrival, such as intense geomagnetic storms. Despite the incremental use of new instrumentation and the development of novel methodologies, ToA estimated errors remain above 10 h on average. Here, we investigate the prediction of the ToA of CMEs using observations from heliospheric imagers, i.e., from heliocentric distances higher than those covered by the existent coronagraphs. In order to perform this work, we analyze 14 CMEs observed by the heliospheric imagers HI-1 onboard the twin STEREO spacecraft to determine their front location and speed. The kinematic parameters are derived with a new technique based on the Elliptical Conversion (ElCon) method, which uses simultaneous observations from the two viewpoints from STEREO. Outside the field of view of the instruments, we assume that the dynamics of the CME evolution is controlled by aerodynamic drag, i.e., a force resulting from the interaction with particles from the background solar wind. To model the drag force, we use a physical model that allows us to derive its parameters without the need to rely on drag coefficients derived empirically. We found a CME ToA mean error of 1.6 +/- 8.0 h ToA and a mean absolute error of 6.9 +/- 3.9 h for a set of 14 events. The results suggest that observations from HI-1 lead to estimates with similar errors to observations from coronagraphs. (AU)

Processo FAPESP: 18/21657-1 - Estudo da variabilidade da atividade auroral em rádio da magnetosfera de Júpiter
Beneficiário:Ezequiel Echer
Modalidade de apoio: Auxílio à Pesquisa - Regular
Processo FAPESP: 14/24711-6 - Estudo conjunto de ejeções coronais de massa e suas estruturas correspondentes nas vizinhanças da Terra
Beneficiário:Carlos Roberto Braga
Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
Processo FAPESP: 17/21270-7 - Forças atuantes na propagação de ejeções coronais de massa
Beneficiário:Carlos Roberto Braga
Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado