Evolution of lower-hybrid-driven current during the formation of an internal transport barrier.
Evolution of the lower-hybrid(LH)-driven current profile was measured during the formation of an internal transport barrier (ITB) in a reversed magnetic shear discharge. As the ITB developed, the initially centrally peaked LH-driven current profile gradually turned hollow and was sometimes accompanied by an off-axis peak in the electron temperature profile. These observations indicate the concentration of LH power deposition to the ITB for this case as a result of nonlinear coupling between the LH waves and the target plasma.
Japan Atomic Energy Research Institute, 801-1 Mukouyama, Naka-machi, Naka-gun, Ibaraki 311-0193, Japan.
O
O
Naito
Z
Z
Cui
S
S
Ide
T
T
Suzuki
T
T
Oikawa
M
M
Seki
T
T
Hatae
T
T
Fujita
T
T
Kondoh
H
H
Shirai
Y
Y
Ikeda
K
K
Ushigusa