National Aeronautics and Space Administration

Living With A Star

Targeted Research and Technology

A New Kinetic Model for Coronal Heating and Generation of the Fast Solar Wind by Ion-Cyclotron Resonance

ROSES ID: NRA-00-OSS-01      Selection Year: 2001      

Program Element: Independent Investigation: LWS

Principal Investigator: Phillip A. Isenberg

Affiliation(s): University of New Hampshire

Summary:

The solar wind directly controls the properties of the Earth's plasma environment, as well as fundamentally mediating all the energetic plasma disturbances, from coronal mass ejections to cosmic rays, which affect our life and society. The heating and acceleration of the ions in coronal holes, which produces the basic fast solar wind, has been the subject of intense investigation for many years. The process which seems most likely to explain this heating is the cyclotron-resonant dissipation of ion-cyclotron waves. Many theoretical models incorporating this mechanism have been able to reproduce the fluid properties of the fast wind, but very little of this work has considered the detailed kinetics of this resonant interaction.
Recently, we presented a new analytical description of the kinetic response of collisionless coronal ions to the resonant cyclotron interaction. This 'kinetic shell' picture uses the reasonable assumption that the resonant response of the ions occurs much faster than the non-resonant processes in the corona. Our initial investigations of this assumption were very encouraging, and lead to a number of promising suggestions for modeling the generation and kinetic evolution of the fast solar wind.
Here, we propose a three-year project to develop a comprehensive quantitative model of the generation of the fast solar wind, using this kinetic shell formalism. We will undertake a series of well-defined steps to extend our initial calculations, adding in stages the effects of inward-propagating waves, dispersion, and heavy ions. Qualitative analysis has already shown that this model can produce a realistic fast wind with a minimum of free parameters, as well as detailed new explanations for the presence of the secondary proton beam and the preferential heating of heavy ions.
Ultimately, this model will provide rigorous tests of the resonant cyclotron heating mechanism, and will serve as a valuable operational tool to guide future observations. This understanding of the kinetic origins of the solar wind is a necessary foundation on which to build models and predictions of more complicated behavior of the heliospheric medium.

Publications:

Performance YearReferenceInvestigation TypeActions
1Isenberg, Philip A.; Lee, Martin A.; Hollweg, JosephÂ...
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1Isenberg, Philip A.; (2001), The kinetic shell model of c...
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1Hollweg, Joseph V.; Isenberg, Philip A.; (2002), Genera...
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Presentations:

Performance YearReferenceActions
1Isenberg, Phillip A.; (2001), Heating of Coronal Holes a...
1Isenberg, P. A.; (2001), The Kinetic Shell Model of Corona...

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