ISSN:
1089-7666
Source:
AIP Digital Archive
Topics:
Physics
Notes:
In this paper results from the initial operation of the JET tokamak [Plasma Physics and Controlled Nuclear Fusion Research (IAEA, Vienna, 1985), Vol. 1, p. 11] with beryllium are summarized. JET was first operated with an evaporated Be coating on the walls and graphite limiters in June 1989. In August the graphite limiter tiles were replaced with the Be tiles, and a three week experimental campaign was conducted in September/October. In the first phase oxygen was reduced to a negligible level and the carbon flux halved. In the second phase, for limiter mode operation, carbon was reduced by another factor of 5, and Be became the dominant impurity. High-power, long-pulsed additionally heated limiter mode discharges with Zeff 〈1.5 were achieved, and density limits were increased by a factor of up to 2. Ion cyclotron resonance frequency (ICRF)-produced H modes were obtained in X-point operation (double null). The combination of Be gettering with new operational procedures to delay the strong influx of carbon from the X-point tiles enables the achievement of record fusion parameters in H-mode discharges including a transient ndTiτE value of 9×1020 m−3 keV sec, corresponding to a QDT equivalent of about 0.8.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.859585
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