The quotation is from the summary lecture presented by Lev Artsimovich at the 1961 IAEA Conference in Salzburg. Here then is our continuing Report from Purgatory, Issue number 7, Chapter 1, Magnetic Confinement Experiments.

Measurements of deuterium retention in samples of lithium exposed in the liquid state to deuterium plasma are reported. Retention was measured as a function of plasma ion dose in the range 6×1019–4×1022 D atoms and exposure temperature between 523 and 673 K using thermal desorption spectrometry. The results are consistent with the full uptake of all deuterium ions incident on the liquid metal surface and are found to be independent of the temperature of the liquid lithium over the range explored. Full uptake, consistent with very low recycling, continues until the sample is volumetrically converted to lithium deuteride. This occurs for exposure temperatures where the gas pressure during exposure was both below and slightly above the corresponding decomposition pressure for LiD in Li.

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Positive radial electric fields have been created at the edge of the TEXTOR tokamak plasma using an electrode. The electric field induces a thin (δr ∼ 1.5 cm), E × B driven layer at the edge rotating poloidally at 12-20 km/s and featuring high shear. Concomitant changes in the density and poloidal electric field fluctuations and their cross-phase in the shear layer result in suppression of radial turbulent particle transport, even at low radial electric field strength. Temperature fluctuations are reduced, resulting in diminished turbulent heat flux. As turbulent particle transport is quenched, the particle confinement time τp increases by a factor of 2 and the energy confinement time τE by 20%. Turbulent transport accounts for ∼50% of the total particle flux. Both the cross-phase and the density fluctuations are sensitive to the sign of ∇Er.

A new set of two-fluid equations that are valid from collisional to weakly collisional limits is derived. Starting from gyrokinetic equations in flux coordinates with no zero-order drifts, a set of moment equations describing plasma transport along the field lines of a space- and time-dependent magnetic field is derived. No restriction on the anisotropy of the ion distribution function is imposed. In the highly collisional limit, these equations reduce to those of Braginskii, while in the weakly collisional limit they are similar to the double adiabatic or Chew, Goldberger, and Low (CGL) equations [Proc. R. Soc. London, Ser. A 236, 112 (1956)]. The new set of equations also exhibits a physical singularity at the sound speed. This singularity is used to derive and compute the sound speed. Numerical examples comparing these equations with conventional transport equations show that in the limit where the ratio of the mean free path λ to the scale length of the magnetic field gradient LB approaches zero, there is no significant difference between the solution of the new and conventional transport equations. However, conventional fluid equations, ordinarily expected to be correct to the order (λ/LB)2, are found to have errors of order (λ/Lu)2 =(λ/LB)2/(1−M2)2, where Lu is the scale length of the flow velocity gradient and M is the Mach number. As such, the conventional equations may contain large errors near the sound speed (M≊1).