Tilt mode stability scaling in field-reversed configurations with finite Larmor radius effect
- Department of Environmental Science, Faculty of Science, Niigata University, Ikarashi, Niigata 950-2181, (Japan)
- University of Washington, Redmond Plasma Physics Laboratory, Redmond, Washington 98052 (United States)
The marginal stability of a static plasma with finite-Larmor-radius (FLR) effects depends on a combination of the FLR effect and the ideal magnetohydrodynamic (MHD) potential energy. For the tilt mode in a field-reversed configuration (FRC) previous computations of these two factors led to a prediction of stability for S{sub *}{<=}(3-5)E where S{sub *} is the macroscale parameter (separatrix radius/ion skin depth) and E is the elongation (separatrix half length/separatrix radius). This prediction explained the observed stability of most experiments. However, recent computations of actual MHD eigenfunctions indicate that the MHD growth rate has a much weaker scaling with elongation than previously believed. As a consequence, most of the long-lived, stable FRC experiments lie in the region predicted to be unstable. It appears then that the stability of FRC experiments is not explained by FLR effects in a static equilibrium. (c) 2000 American Institute of Physics.
- OSTI ID:
- 20215455
- Journal Information:
- Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 3 Vol. 7; ISSN PHPAEN; ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
Similar Records
The tilt mode, turbulence and transport in field-reversed configurations
Inappropriateness of the finite Larmor radius model for the tilting mode in field reversed configurations