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10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Field-reversed configurations in an unmagnetized plasma.
R L Stenzel1, J M Urrutia, K D Strohmaier
1Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547, USA. stenzel@physics.ucla.edu
Physical Review Letters
|October 15, 2008
Summary
Applying oscillating magnetic fields to unmagnetized plasma magnetizes electrons, enabling deeper penetration via whistler modes. This process forms field-reversed configurations and energizes electrons, creating high-frequency oscillations.
Area of Science:
- Plasma Physics
- Magnetohydrodynamics
- Electromagnetism
Background:
- Unmagnetized plasmas exhibit limited magnetic field penetration.
- Understanding plasma behavior under oscillating magnetic fields is crucial for fusion energy and astrophysics.
Purpose of the Study:
- To investigate the interaction of oscillating magnetic fields with unmagnetized plasmas.
- To explore the mechanisms of magnetic field penetration and plasma magnetization.
- To characterize the formation of field-reversed configurations and associated plasma dynamics.
Main Methods:
- Application of an oscillating magnetic field using a loop antenna to an unmagnetized plasma.
- Observation of field penetration at varying amplitudes.
- Analysis of electron magnetization and plasma response.
Main Results:
- At small amplitudes, the magnetic field is evanescent.
- At large amplitudes, electrons become magnetized, allowing deeper field penetration through whistler modes.
- Field-reversed configurations are formed transiently during each half cycle.
- Electron energization and high-frequency oscillations are observed due to transient whistler instabilities.
Conclusions:
- Electron magnetization is key to enhanced magnetic field penetration in plasmas.
- Oscillating magnetic fields can induce complex structures like field-reversed configurations.
- The study reveals novel plasma dynamics driven by whistler instabilities.
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