Yh. Xu et al., ELECTROSTATIC FLUCTUATIONS AND RELATED TRANSPORT IN THE EDGE AND COREPLASMA OF THE KEDA TOKAMAK-5C, Physics of plasmas, 3(3), 1996, pp. 1022-1028
Using the swept double probe and triple probe technique, temperature,
density and potential fluctuations have been measured in both the plas
ma edge and core of the Keda Tokamak-5C (KT-5C) [World Survey of Activ
ities in Controlled Fusion Research, Nuclear Fusion Special Supplement
(International Atomic Energy Agency, Vienna, 1991), p. 190]. The fluc
tuation-driven particle and energy fluxes were also estimated from the
correlations of [(n) over tilde(e) (E) over tilde(theta)] and [(T) ov
er tilde(e) (E) over tilde(theta)]. Evidence has been found that there
exist substantial electron temperature fluctuations of (T) over tilde
(e)/T-e similar or equal to 0.4 (n) over tilde(e)/n(e) in both regions
. At the edge of KT-5C, many of the fluctuation features, such as the
velocity shear stabilization of turbulence, the non-Boltzmann relation
and the role of fluctuations in the edge confinement, are very simila
r to those obtained from other tokamaks. In the plasma interior, the f
luctuations do obey the simple Boltzmann relationship and the profiles
of the normalized fluctuating levels (n) over tilde(e)/n(e) and <(phi
)over tilde>/T-e vary roughly as (n) over tilde(e)/n(e) proportional t
o n(e)(-3/2) and <(phi)over tilde>(p)/T-e proportional to n(e)(-1/2)T(
e)(-1), respectively. In addition, a spiky, radially intermittent stru
cture in the particle and energy fluxes with large levels at the low-q
resonances and lower levels in between was found. The experimental re
sults provide some new evidence, particularly in the plasma core, for
a better understanding of the basic mechanism of turbulence. (C) 1996
American Institute of Physics.