Characterization of the turbulent magnetic integral length in the solar wind: from 0.3 to 5 astronomical units

The solar wind is a structured and complex system, in which the fields vary strongly over a wide range of spatial and temporal scales. As an example, the turbulent activity in the wind affects the evolution in the heliosphere of the integral turbulent scale or correlation length [λ], usually associa...

ver descrição completa

Detalhes bibliográficos
Autores: Ruiz, Maria Emilia; Dasso, Sergio Ricardo; Matthaeus, W. H.; Weygand, J. M.
Tipo de documento: Artigo
Estado:Published version
Data de publicação:2014
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositório:CONICET Digital (CONICET)
Idioma:Inglês
OAI Identifier:oai:ri.conicet.gov.ar:11336/16455
Acesso em linha:http://hdl.handle.net/11336/16455
Nível de acesso:Acesso aberto
Palavra-chave:Magnetohydrodynamics
Turbulence
Magnetic Fields, Interplanetary
Solar Wind, Theory
Coronal Mass Ejections, Interplanetary
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descrição
Resumo:The solar wind is a structured and complex system, in which the fields vary strongly over a wide range of spatial and temporal scales. As an example, the turbulent activity in the wind affects the evolution in the heliosphere of the integral turbulent scale or correlation length [λ], usually associated with the breakpoint in the turbulent-energy spectrum that separates the inertial range from the injection range. This large variability of the fields demands a statistical description of the solar wind. We study the probability distribution function (PDF) of the magnetic-autocorrelation lengths observed in the solar wind at different distances from the Sun. We used observations from the Helios, ACE, and Ulysses spacecraft. We distinguished between the usual solar wind and one of its transient components (interplanetary coronal mass ejections, ICMEs), and also studied solar-wind samples with low and high proton beta [βp]. We find that in the last three regimes the PDF of λ is a log-normal function, consistent with the multiplicative and nonlinear processes that take place in the solar wind, the initial λ (before the Alfvénic point) being larger in ICMEs.