Sawtooth stabilization experiments by ICRF heating alone and its combination with NBI or LHCD in JT-60U

Conference · Sat Oct 15 04:00:00 EDT 1994 · AIP Conference Proceedings (American Institute of Physics); (United States)

OSTI ID:6689850

Kimura, H; Fujii, T; Sato, M; Nemoto, M; Hamamatsu, K; Kondoh, T; Matsuoka, M; Moriyama, S; Saigusa, M; Takeuchi, H; Ushigusa, K ^[1]; Campbell, D J ^[2]

---

1. Japan Atomic Energy Research Institute, Naka, Naka, Ibaraki, Japan 311-01 (Japan)
2. JET Joint Undertaking, Arbingdon, Oxfordshire OX14 3EA (United Kingdom)

Extension of an operation range for the sawtooth stabilization by a second harmonic minority ion ICRF heating is being pursued in JT-60U. The sawtooth stabilization is obtained at relatively high density ([bar n][sub e][similar to]3.8[times]10[sup 19] m[sup [minus]3]) and low-q (q[sub eff]=4 at I[sub p]=2.4 MA) for OH target plasmas with only 2.8 MW of ICRF power. The sawtooth stabilization is thus obtained at high [l angle]n[sub e][r angle]/P[sub tot] value of 0.8[times]10[sup 19] m[sup [minus]3] mW[sup [minus]1], which is notably larger than the value achieved on JET, where fundamental resonance minority ion heating is employed. Another peculiar effect of the second harmonic heating is that stabilization occurs only after the inversion radius expands sufficiently, i.e., r[sub inv]/a[ge]0.26. The sawtooth stabilization by ICRF heating becomes easier with NBI-heated target plasmas (longest stable period up to 1.7 sec), while it tends to be difficult with the LHCD target plasmas.

• OSTI ID: 6689850
• Report Number(s): CONF-9304112--
• Conference Information: Journal Name: AIP Conference Proceedings (American Institute of Physics); (United States) Journal Volume: 289:1
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700350 -- Plasma Production
Heating
Current Drive
& Interactions-- (1992-)
700460* -- Fusion Technology-- Heating & Fueling Systems
BEAM INJECTION
CLOSED PLASMA DEVICES
CYCLOTRON HARMONICS
Fu
Fuels-- (1992)
HARMONICS
HEATING
HIGH-FREQUENCY HEATING
ICR HEATING
JT-60 TOKAMAK
LOWER HYBRID HEATING
NEUTRAL ATOM BEAM INJECTION
OSCILLATIONS
PLASMA HEATING
SAWTOOTH OSCILLATIONS
THERMONUCLEAR DEVICES
TOKAMAK DEVICES