Jc. Forster et al., STUDY OF DENSITY AND POTENTIAL FLUCTUATIONS IN THE TEXT TOKAMAK WITH A HEAVY-ION BEAM PROBE, IEEE transactions on plasma science, 22(4), 1994, pp. 359-362
A heavy ion beam probe was used to study the characteristics of densit
y and potential fluctuations in the TEXT tokamak. Fluctuations of dens
ity and space potential are nearly Boltzmann like, (n) over tilde/n si
milar to <(phi)over tilde>/kT(e), near the edge of the plasma (0.8 < r
/a < 0.9). Potential fluctuations are proportionally greater in the ed
ge region (r/a > 0.9). The turbulent E x B radial particle flux is suf
ficient to account for all of the particle loss from the tokamak. No p
oloidal asymmetries, within a poloidal angle range of about 70 degrees
, are observed in the fluctuation levels. The fluctuation spectral sha
pe, the density potential phase angle, and the fluctuation propagation
speed show a strong radial dependence.