Heating of coronal active regions

Recent observations of coronal loops in solar active regions show that their heating must be a truly dynamic process. Even though it seems clear that the energy source is the magnetic field that confines the coronal plasma, the details of how it dissipates are still a matter of debate. In this prese...

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Detalhes bibliográficos
Autor: Gómez, D.O.
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Argentina
Recursos:Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
Repositorio:Biblioteca Digital (UBA-FCEN)
Idioma:inglés
OAI Identifier:paperaa:paper_17439213_v6_nS273_p44_Gomez
Acesso em linha:http://hdl.handle.net/20.500.12110/paper_17439213_v6_nS273_p44_Gomez
Access Level:acceso abierto
Palavra-chave:Magnetic fiels
MHD
Sun: corona
Sun: X-rays
Turbulence
Descrição
Resumo:Recent observations of coronal loops in solar active regions show that their heating must be a truly dynamic process. Even though it seems clear that the energy source is the magnetic field that confines the coronal plasma, the details of how it dissipates are still a matter of debate. In this presentation we review the theoretical models of coronal heating, which have been traditionally clasified as DC or AC depending on the electrodynamic response of the loops to the photospheric driving motions. Also, we show results from numerical simulations of the internal dynamics of coronal loops within the framework of the reduced MHD approximation. These simulations indicate that the application of a stationary velocity field at the photospheric boundary leads to a turbulent stationary regime after several photospheric turnover times. Once this turbulent regime is set, both DC and AC stresses dissipate at faster rates as a result of a direct energy cascade. © International Astronomical Union 2011.