On the dynamics of the power spectrum during lower hybrid current drive in tokamaks
The propagation and absorption of the power spectrum during lower hybrid current drive in tokamaks is investigated. A combined ray tracing and Fokker-Planck code is utilised and stochastic effects induced by toroidicity are correctly taken into account by using a large number of rays. It is shown that when strong wave damping prevails, the absorbed spectrum is very similar in shape to the launched one, although some broadening and shifting in parallel wave index generally occur, and power deposition is localised. If the wave damping is weak and stochastic effects are important, rays end up sweeping the entire plasma cross-section, power deposition is extended, and the absorbed spectrum is much broader than the launched one.
Bibliographic Reference: Report: EUR-CEA-FC-1475 EN (1993) 15 pp.
Availability: Available from CEA, Département de Recherches sur la Fusion Contrôlée, Saint-Paul-lez-Durance (FR)
Record Number: 199310378 / Last updated on: 1994-11-29
Original language: en
Available languages: en