Anomalous electron transport and lower-hybrid wave damping

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Abstract
The transport of electrons across magnetic fields was investigated by two‐dimensional computer experiments. Under the modest condition ωce≈ωpe, which occurs in many laboratory plasmas and fusion devices, it is found that the electron heat and momentum transport rates are much enhanced above the classical collisional values even for plasma very close thermal equilibrium. The enhancement is due to electron turbulent motion in the fields of thermally excited lower hybrid waves. Nonthermal plasmas could show an even larger degree of enhanced transport. Employing a fluid model which includes turbulent viscous terms in the electron momentum equation, linearized theory gives predictions which are in reasonably good agreement with the observed wave damping. The computer results throw some light on the theory of strong turbulence, comparison with such theories points up some discrepancies and indicates the proper method for including the turbulence effects. Estimates of the electron heat transport in three‐dimensional thermonuclear plasmas due to this mechanism gives values comparable to those predicted by neclassical theory from thermal fluctuations alone; enhancement of the fluctuations above the thermal level will given higher transport rates. These results suggest that nonclassical effects can be very important in plasma transport and could be important for fusion plasmas.