1 - Nuclear Sciences and Applications - IAEA

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IAEA-CN-50/A-I-4 79
LIM
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SP6CT
-HUM
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P[_H (MW)
J7G. 70. LH current drive characteristics.
Current ramp-up by the LH wave [3] has been investigated in low density divertor
discharges, and the plasma current was ramped up from 0.46 to 0.60 MA
in 6.4 s at r^ = 0.3 X 10 19 m" 3 with an injected LH power of 1.6 MW. It is estimated
for this discharge that about 5 % of the LH wave energy is transferred to the
poloidal field energy of the driven current.
Current profile modification is another important aspect of current drive [10].
Improved confinement exceeding L-mode scaling has been observed for flattened
current profiles induced by LH wave injection, when the change in the internal inductance
reached A*- « -0.1.
9. FUTURE PROGRAMME OF JT-60
A major role to be played by JT-60 in the future is the improvement of the tokamak
plasma performance so that the Japanese fusion programme can be advanced to
reach the next step ignition device. The JT-60 upgrade programme [11] has started
already; in this programme, the vacuum vessel and the poloidal field coil will be
replaced completely in order to allow high current discharges with 6 MA in a divertor
and with 7 MA in a limiter configuration.
Deuterium beams will be injected into deuterium instead of hydrogen plasmas
in the upgrade experiment. In conjunction with the change in the beam species, the
beam power is expected to increase up to 40 MW at a beam energy of 120 keV. An
RF heating system such as LHRF and ICRF will also be set up with some improvements
in various devices.