Hopf bifurcations in coronal loops I. Stability conditions for static equilibrium

We study the coupling between the hot plasma confined in a coronal loop and the much colder chromospheric plasma at the footpoints. Considering the coronal heating rate as a control parameter, we find that the static equilibrium becomes unstable for heating rates below a critical value, giving rise...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Gomez, Daniel Osvaldo, Sicardi Schifino, Aníbal Carlos, Ferro Fontán, Constantino
Publicado: 1990
Materias:
Hydromagnetics
Sun: corona
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v352_n1_p318_Gomez
http://hdl.handle.net/20.500.12110/paper_0004637X_v352_n1_p318_Gomez
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
id paper:paper_0004637X_v352_n1_p318_Gomez
record_format dspace
spelling paper:paper_0004637X_v352_n1_p318_Gomez2023-06-08T14:28:30Z Hopf bifurcations in coronal loops I. Stability conditions for static equilibrium Gomez, Daniel Osvaldo Sicardi Schifino, Aníbal Carlos Ferro Fontán, Constantino Hydromagnetics Sun: corona We study the coupling between the hot plasma confined in a coronal loop and the much colder chromospheric plasma at the footpoints. Considering the coronal heating rate as a control parameter, we find that the static equilibrium becomes unstable for heating rates below a critical value, giving rise to the appearance of a stable limit cycle. Starting from the hydrodynamic equations, we derive a model which generalizes the analysis of Kuin and Martens and consistently takes into account the condensation-evaporation process. In this paper, we linearize our equations in order to find the bifurcation point where the stability of the static equilibrium is lost. We also show that this model can provide a natural explanation for the excess widths of EUV spectral lines formed in the transition region. Moreover, we can predict the observed reduction in the broadening of these lines when they form in certain active regions, like quiescent prominences or sunspots. Fil:Gómez, D. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Sicardi Schifino, A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Ferro Fontán, C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 1990 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v352_n1_p318_Gomez http://hdl.handle.net/20.500.12110/paper_0004637X_v352_n1_p318_Gomez
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Hydromagnetics
Sun: corona
spellingShingle Hydromagnetics
Sun: corona
Gomez, Daniel Osvaldo
Sicardi Schifino, Aníbal Carlos
Ferro Fontán, Constantino
Hopf bifurcations in coronal loops I. Stability conditions for static equilibrium
topic_facet Hydromagnetics
Sun: corona
description We study the coupling between the hot plasma confined in a coronal loop and the much colder chromospheric plasma at the footpoints. Considering the coronal heating rate as a control parameter, we find that the static equilibrium becomes unstable for heating rates below a critical value, giving rise to the appearance of a stable limit cycle. Starting from the hydrodynamic equations, we derive a model which generalizes the analysis of Kuin and Martens and consistently takes into account the condensation-evaporation process. In this paper, we linearize our equations in order to find the bifurcation point where the stability of the static equilibrium is lost. We also show that this model can provide a natural explanation for the excess widths of EUV spectral lines formed in the transition region. Moreover, we can predict the observed reduction in the broadening of these lines when they form in certain active regions, like quiescent prominences or sunspots.
author Gomez, Daniel Osvaldo
Sicardi Schifino, Aníbal Carlos
Ferro Fontán, Constantino
author_facet Gomez, Daniel Osvaldo
Sicardi Schifino, Aníbal Carlos
Ferro Fontán, Constantino
author_sort Gomez, Daniel Osvaldo
title Hopf bifurcations in coronal loops I. Stability conditions for static equilibrium
title_short Hopf bifurcations in coronal loops I. Stability conditions for static equilibrium
title_full Hopf bifurcations in coronal loops I. Stability conditions for static equilibrium
title_fullStr Hopf bifurcations in coronal loops I. Stability conditions for static equilibrium
title_full_unstemmed Hopf bifurcations in coronal loops I. Stability conditions for static equilibrium
title_sort hopf bifurcations in coronal loops i. stability conditions for static equilibrium
publishDate 1990
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v352_n1_p318_Gomez
http://hdl.handle.net/20.500.12110/paper_0004637X_v352_n1_p318_Gomez
work_keys_str_mv AT gomezdanielosvaldo hopfbifurcationsincoronalloopsistabilityconditionsforstaticequilibrium
AT sicardischifinoanibalcarlos hopfbifurcationsincoronalloopsistabilityconditionsforstaticequilibrium
AT ferrofontanconstantino hopfbifurcationsincoronalloopsistabilityconditionsforstaticequilibrium
_version_ 1768543588758585344

Ejemplares similares