EXPLOSIVE INSTABILITY AND CORONAL HEATING
Abstract
The observed energyloss rate from the solar corona implies that the coronal magnetic field has a critical angle at which energy is released. It has been hypothesized that at this critical angle an 'explosive instability' would occur, leading to an enhanced conversion of magnetic energy into heat. In earlier investigations, we have shown that a sheardependent magnetohydrodynamic process called 'secondary instability' has many of the distinctive features of the hypothetical 'explosive instability'. In this paper, we give the first demonstration that this 'secondary instability' occurs in a system with linetied magnetic fields and boundary shearingbasically the situation described by Parker. We also show that, as the disturbance due to secondary instability attains finite amplitude, there is a transition to turbulence which leads to enhanced dissipation of magnetic and kinetic energy. These results are obtained from numerical simulations performed with a new parallelized, viscoresistive, threedimensional code that solves the cold plasma equations. The code employs a Fourier collocationfinite difference spatial discretization, and uses a thirdorder RungeKutta temporal discretization.
 Authors:
 Laboratory for Computational Physics and Fluid Dynamics, Naval Research Laboratory, Washington, DC 203755344 (United States)
 Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States)
 Publication Date:
 OSTI Identifier:
 21367361
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Astrophysical Journal; Journal Volume: 704; Journal Issue: 2; Other Information: DOI: 10.1088/0004637X/704/2/1059
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COLD PLASMA; COMPUTERIZED SIMULATION; ENERGY LOSSES; EQUATIONS; EXPLOSIVE INSTABILITY; KINETIC ENERGY; MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; SOLAR CORONA; SUN; THREEDIMENSIONAL CALCULATIONS; TURBULENCE; ATMOSPHERES; ENERGY; FLUID MECHANICS; HYDRODYNAMICS; INSTABILITY; LOSSES; MAIN SEQUENCE STARS; MECHANICS; PLASMA; PLASMA INSTABILITY; SIMULATION; SOLAR ATMOSPHERE; STARS; STELLAR ATMOSPHERES; STELLAR CORONAE
Citation Formats
Dahlburg, R. B., Liu, J.H., Klimchuk, J. A., and Nigro, G., Email: rdahlbur@lcp.nrl.navy.mi. EXPLOSIVE INSTABILITY AND CORONAL HEATING. United States: N. p., 2009.
Web. doi:10.1088/0004637X/704/2/1059.
Dahlburg, R. B., Liu, J.H., Klimchuk, J. A., & Nigro, G., Email: rdahlbur@lcp.nrl.navy.mi. EXPLOSIVE INSTABILITY AND CORONAL HEATING. United States. doi:10.1088/0004637X/704/2/1059.
Dahlburg, R. B., Liu, J.H., Klimchuk, J. A., and Nigro, G., Email: rdahlbur@lcp.nrl.navy.mi. Tue .
"EXPLOSIVE INSTABILITY AND CORONAL HEATING". United States.
doi:10.1088/0004637X/704/2/1059.
@article{osti_21367361,
title = {EXPLOSIVE INSTABILITY AND CORONAL HEATING},
author = {Dahlburg, R. B. and Liu, J.H. and Klimchuk, J. A. and Nigro, G., Email: rdahlbur@lcp.nrl.navy.mi},
abstractNote = {The observed energyloss rate from the solar corona implies that the coronal magnetic field has a critical angle at which energy is released. It has been hypothesized that at this critical angle an 'explosive instability' would occur, leading to an enhanced conversion of magnetic energy into heat. In earlier investigations, we have shown that a sheardependent magnetohydrodynamic process called 'secondary instability' has many of the distinctive features of the hypothetical 'explosive instability'. In this paper, we give the first demonstration that this 'secondary instability' occurs in a system with linetied magnetic fields and boundary shearingbasically the situation described by Parker. We also show that, as the disturbance due to secondary instability attains finite amplitude, there is a transition to turbulence which leads to enhanced dissipation of magnetic and kinetic energy. These results are obtained from numerical simulations performed with a new parallelized, viscoresistive, threedimensional code that solves the cold plasma equations. The code employs a Fourier collocationfinite difference spatial discretization, and uses a thirdorder RungeKutta temporal discretization.},
doi = {10.1088/0004637X/704/2/1059},
journal = {Astrophysical Journal},
number = 2,
volume = 704,
place = {United States},
year = {Tue Oct 20 00:00:00 EDT 2009},
month = {Tue Oct 20 00:00:00 EDT 2009}
}

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