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(EXP3/20) Collisional Transport in Nonneutral Plasmas

D. H. E. Dubin

Department of Physics, University of California, San Diego, La Jolla, California 92093-0319, USA

Abstract.  Classical transport theory grossly underestimates collisionally-driven cross-field transport for plasmas in the parameter regime of r_c $\ll$ $\lambda_{D}^{}$, where r_c $\equiv$ $\overline{v}$/$\Omega_{c}^{}$, $\lambda_{D}^{2}$ $\equiv$ T/4$\pi$e²n. In current experiments operating in this regime, cross-field test particle transport is observed to be a factor of 10 larger than the prediction of classical theory. Heat conduction is enhanced by up to 300 times over classical theory, and viscosity is up to 10⁴ times larger. New guiding center theories of transport due to long-range collisions have been developed that agree with the measurements. Theory also predicts that emission and absorption of plasma waves may further enhance the thermal conduction and viscosity, providing a possible mechanism for anomalous thermal conductivity in the electron channel of fusion plasmas.

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