Observation of two wave induced chaos in a magnetized plasma
It has been shown theoretically and experimentally that in a magnetised plasma a wave propagating at a finite angle with respect to the B-field can generate chaos in particle orbits and, consequently, fast ion heating. The case of two (or more) waves propagating at different phase velocities is predicted to be more efficient for heating: the threshold amplitude for the occurrence of chaos should be lower, due to a large number of resonances in phase space. This experiment investigates the interaction between ions and two propagating electrostatic modes in a Q-machine plasma. In particular, the aim is to perform and integrate observations of the collective ion response (wave characteristics), of ion kinetic features (modification of the distribution functions, time scale for heating) and of single particle orbit modifications (phase space transport), using optical measurements at different scales, from the single particle to the macroscopic. It is found that chaos appears to be limited by self-consistent effects, i.e. by mutual interactions between wave and particles.
Bibliographic Reference: Paper presented: 19th EPS Conference on Controlled Fusion and Plasma Physics, Innsbruck (AT), June 29 - July 3, 1992
Availability: Available from (1) as Paper EN 36861 ORA
Record Number: 199210697 / Last updated on: 1994-12-02
Original language: en
Available languages: en