Suppression of large edge-localized modes in high-confinement DIII-D plasmas with a stochastic magnetic boundary.
A stochastic magnetic boundary, produced by an applied edge resonant magnetic perturbation, is used to suppress most large edge-localized modes (ELMs) in high confinement (H-mode) plasmas. The resulting H mode displays rapid, small oscillations with a bursty character modulated by a coherent 130 Hz envelope. The H mode transport barrier and core confinement are unaffected by the stochastic boundary, despite a threefold drop in the toroidal rotation. These results demonstrate that stochastic boundaries are compatible with H modes and may be attractive for ELM control in next-step fusion tokamaks.
Evans
T E
TE
General Atomics, San Diego, California, USA.
Moyer
R A
RA
Thomas
P R
PR
Watkins
J G
JG
Osborne
T H
TH
Boedo
J A
JA
Doyle
E J
EJ
Fenstermacher
M E
ME
Finken
K H
KH
Groebner
R J
RJ
Groth
M
M
Harris
J H
JH
La Haye
R J
RJ
Lasnier
C J
CJ
Masuzaki
S
S
Ohyabu
N
N
Pretty
D G
DG
Rhodes
T L
TL
Reimerdes
H
H
Rudakov
D L
DL
Schaffer
M J
MJ
Wang
G
G
Zeng
L
L