EURATOM-CEA Association contributions to the 13th IAEA International Conference on Plasma Physics and Controlled Nuclear Fusion Research
The first paper presented in this report is concerned with progress to long pulse operation in Tore Supra. The modification of plasma boundary conditions by pump limiter or ergodic divertor was investigated. Lower hybrid waves with power up to 3.8 MW were launched driving up to 80% of the total current, thus extending the plateau current to 22s. The time constants involved in the control of steady state plasmas (heat, particle and current diffusion) are discussed. The second paper gives details of ergodic divertor experiments in Tore Supra. The ergodic divertor creates a magnetic perturbation which changes the transport in the edge layer. The experiments show that the edge temperature is reduced and that the power is channelled to the neutraliser plates. The reduced plasma density and carbon density are correlated to a reduced particle lifetime at the very edge of the plasma. In the third paper, Hamiltonian formalism is used to analyse the direct resonant interaction between the fast magnetosonic wave and the passing electrons in a tokamak. The regions in phase space where quasilinear diffusion applies are deduced from a stochasticity criterion. A singular behaviour of rational-q surfaces is found and the implications for the fast wave current drive scenario in a reactor are discussed.
Bibliographic Reference: Report: EUR-CEA-FC-1408 EN (1990) 11 pp.
Availability: Available from CEA, Département de Recherches sur la Fusion Contrôlée, Saint-Paul-lez-Durance (FR)
Record Number: 199110120 / Last updated on: 1994-12-02
Original language: en
Available languages: en