1 - Nuclear Sciences and Applications - IAEA

68 JT-60 TEAM
T. TANAKA, Y. TANAKA, K. TANI, M. TERAKADO, T. TERAKADO,
K. TOBITA, T. TOKUTAKE, T. TOTSUKA, N. TOYOSHIMA,
T. TSUGITA, S. TSUJI, Y. TSUKAHARA, M. TSUNEOKA,
K. UEHARA, M. UMEHARA, Y. URAMOTO, H. USAMI,
K. USHIGUSA, K. USUI, J. YAGYU, M. YAMAMOTO,
O. YAMASHITA, T. YAMAZAKI, K. YOKOKURA, H. YOKOMIZO,
K. YOKOYAMA, M. YOSHIKAWA, H. YOSHIDA, R. YOSHINO,
Y. YOSHIOKA 1 , I. YONEKAWA, T. YONEDA, K. WATANABE,
M.G. BELL 3 , R.J. BICKERTON 4 , W. ENGELHARDT 4 ,
R.J. GOLDSTON 3 , E. KALLNE 4 , J. KALLNE 4 , H.W. KUGEL 3 ,
P.L. MONDINO 4 , F.X. SOLDNER 5 , Y. TAKASE 6 , P.R. THOMAS 4 ,
K.-L. WONG 3
Naka Fusion Research Establishment,
Japan Atomic Energy Research Institute,
Naka-machi, Naka-gun, Ibaraki-ken,
Japan
Abstract
RECENT PROGRESS IN JT-60 EXPERIMENTS.
The paper describes recent progress in confinement, heating and current drive experiments on
JT-60. The performance of JT-60 has been extended with replacement of the first wall by graphite tiles,
addition of a new diveVtor coil, installation of a multiple pellet injector, enhancement of the power supply
capability and high power, long pulse operation of neutral beam and radiofrequency heating systems
up to 30 MW in combined power. The best parameter values achieved is the product ne(0)TET;(0) =
6 x 10 19 m~ 3 -s-keV for a hydrogen limiter plasma at a plasma current of 3.2 MA. An offset linear
relation for the energy confinement is confirmed for limiter, outside divertor and lower single-null
divertor discharges. An improvement of energy confinement was observed in the lower single-null
divertor experiments for high heating power. Efficient acceleration of high energy beam ions was
achieved in combined neutral beam and radiofrequency heating of low density plasmas. Pellet fuelled
high density plasmas could be heated effectively by a lower hybrid wave without occurrence of parametric
instabilities. Plasma current drive up to 2 MA and ramp-up experiments by a lower hybrid wave
were performed successfully. The current drive efficiency was optimized for plasma and wave
parameters. A further enhancement programme for JT-60 is in progress.
1 Seconded.
2 Kyushu University, Fukuoka, Japan.
3 Plasma Physics Laboratory, Princeton University, Princeton, NJ, USA.
4 JET Joint Undertaking, Abingdon, Oxfordshire, United Kingdom.
5 Max-Planck-Institut fur Plasmaphysik, Garching, Federal Republic of Germany.
6 Massachusetts Institute of Technology, Cambridge, MA, USA.