Measurement of the Time Constants of Fast Electron Distributions in the Tore Supra Tokamak

G. Giruzzi , J. Ségui , Thierry Dudok de Wit (1) , Y. Michelot , Y. Peysson , D. Moreau , M. Talvard

1 LPC2E - Laboratoire de Physique et Chimie de l'Environnement et de l'Espace

The fundamental phenomena governing the dynamics of anisotropic electron distributions in a tokamak plasma are investigated. A fast electron tail driven by modulated pulses of lower-hybrid waves is analyzed by a combination of three diagnostics, i.e., hard x rays, electron-cyclotron emission, and transmission. Three different time constants, characterizing radial diffusion, collisional friction, and pitch-angle scattering, respectively, are identified. Two distinct relaxation regimes are observed, related to the degree of anisotropy of the electron distribution.

Domains: Solar and Stellar Astrophysics [astro-ph.SR]; Instrumentation and Methods for Astrophysic [astro-ph.IM]; Data Analysis, Statistics and Probability [physics.data-an]; Space Physics [physics.space-ph]; Plasma Physics [physics.plasm-ph]; Sciences of the Universe [physics]

G. Giruzzi, J. Ségui, Thierry Dudok de Wit, Y. Michelot, Y. Peysson, et al.. Measurement of the Time Constants of Fast Electron Distributions in the Tore Supra Tokamak. Physical Review Letters, 1995, 74 (4), pp.550-553. ⟨10.1103/PhysRevLett.74.550⟩. ⟨insu-03388673⟩