Characteristics of coronal mass ejections in the near Sun interplanetary space

Based on the observations from the Large Angle and Spectrometric Coronagraph (LASCO) on board the Solar and HeliosphericObservatory (SOHO) spacecraft we studied coronal mass ejections (CME) parameters between 6 and 10 solar radii from the Sun.We have developed a new method to obtain the duration, br...

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Detalhes bibliográficos
Autores: Alejandro Lara, Nat Gopalswamy, J. Américo González Esparza
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2004
País:México
Recursos:Universidad Nacional Autónoma de México
Repositório:Redalyc-UNAM
OAI Identifier:oai:redalyc.org:56843110
Acesso em linha:https://www.redalyc.org/articulo.oa?id=56843110
Access Level:Acceso aberto
Palavra-chave:Ciencias de la Tierra
solar activity
Coronal Mass Ejections
Descrição
Resumo:Based on the observations from the Large Angle and Spectrometric Coronagraph (LASCO) on board the Solar and HeliosphericObservatory (SOHO) spacecraft we studied coronal mass ejections (CME) parameters between 6 and 10 solar radii from the Sun.We have developed a new method to obtain the duration, brightness enhancement (above the background) and speed of the leadingpart of the CMEs. These properties are important in order to understand the dynamics of the CMEs near the Sun and theirevolution in the interplanetary space using numerical models. We present the method of analysis and the results of the applicationof this method to a set of 9 halo CMEs observed during 1997. We found that i) the CME speeds obtained with this method are ingood agreement with measurements of other observers, ii) the average time duration of the CME leading part is 8 hrs. and iii) thebrightness maxima decrease with distance as a power law with a mean index of -3.6.