Plasma physics and controlled nuclear fusion research 1974

NUCLEAR

INSTRUMENTS

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METHODS

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(1975)

31I;

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NORTH-HOLLAND

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BOOK REVIEWS Plasma physics and controlled nuclear fusion research 1974, vol. 1, Fifth Conference Proceedings, T o k y o 11-15 N o v e m b e r 1974, (IAEA, Vienna, 1974). T h e present v o l u m e includes the first part o f the papers a n d discussions presented at the fifth international conference organized by the I A E A in the field o f p l a s m a physics a n d controlled fusion. Earlier conferences o f a similar type have been held in Salzburg 1961, C u l h a m 1965, Novosibirsk 1968, a n d M a d i s o n 1971, as d o c u m e n t e d by the I A E A . By its contents this v o l u m e reflects the present large interest in m a g n e t i c p l a s m a c o n f i n e m e n t in toroidal s c h e m e s o f " T o k a m a k " type. It starts with two chapters on T o m a k a k experiments, followed by one chapter o n theoretical a n d experimental investigations on open m a g n e t i c c o n f i n e m e n t schemes o f magnetic m i r r o r type, a n d ends with two chapters o n T o k a m a k theory. I m p o r t a n t results are reported in this v o l u m e on T o k a m a k research, in the f o r m o f high temperatures a n d values o f density a n d c o n f i n e m e n t times achieved in the T F R device at F o n t e n a y a u x - R o s e s as well as in the adiabatic toroidal c o m p r e s s o r A T C

at Princeton. Nevertheless, there are still difficult problems which have so far n o t been fully u n d e r s t o o d , such as the observed " d i s r u p t i v e " instabilities, the p l a s m a density limit, and the observed a n o m a l o u s p l a s m a particle a n d energy losses. Extensive a n d i m p o r t a n t investigations are reported o n these problems, being the result o f an increased international collaboration between theoreticists a n d experimentalists. F u r t h e r i m p o r t a n t a n d related questions are also treated in the papers presented, i.e. those o f neutral b e a m a n d high-frequency heating o f p l a s m a in closed bottles, o f magnetic limiter operation, a n d o f impurities. T h e chapter on open confinement systems is devoted a m o n g other things to p l a s m a stability in respect to loss-cone m o d e s , p l a s m a confinement, neutral b e a m research, feedback stabilization, p l a s m a production, and laser-initiated target experiments. T h e v o l u m e can be considered as a review on the present state o f fusion research on T o k a m a k s and open systems. T h e additional p a r t s o f the international fusion research p r o g r a m m e will be represented by further v o l u m e s o f the conference proceedings which are s o o n to appear. B. LEHNERT

Plasma physics and controlled nuclear fusion research 1974,

metry. T h e K M S F u s i o n team h a s further studied laser compres" sion o f spherical glass shells. T h e s y m m e t r y also appears to be well expressed in reported electron b e a m - d r i v e n pellet implosions. Collective t r a n s p o r t o f p l a s m a in a magnetic field has been analysed theoretically, leading to estimates o f the loss rates due to convection, wave m o t i o n s and instabilities. Further, the effects o f penetrating neutral gas on p l a s m a equilibrium a n d stability n o w attract an increasing interest, as well as the gas blanket concept o f a confined p l a s m a at intermediate a n d high ion densities. A m o n g the new trends described in this volume, the multimirror m a g n e t i c confinement s c h e m e developed in Novosibirsk s h o u l d be especially mentioned. A n o t h e r modified magnetic mirror a p p r o a c h is represented by adiabatic radio-frequency plugging as developed in N a g o y a . A steadily increasing effort is devoted to fusion reactor technology. In a special session o f the conference, p l a s m a impurities a n d wall erosion have been treated, as well as start-up p r o b l e m s in toroidal fusion reactors. In particular, a suggestion to use silicon carbide and graphite materials s h o u l d be m e n t i o n e d in this connection. T h e last v o l u m e o f the conference proceedings is soon to appear.

vol. 2, Fifth Conference Proceedings, Tokyo, 11-15 N o v e m b e r 1974 ( I A E A , Vienna, 1975). This v o l u m e includes the second part o f the papers a n d discussions presented at the fifth international conference organized by the I A E A in the field o f p l a s m a physics a n d controlled fusion. It contains reports on low-beta toroidal magnetic confinement systems a n d inertial confinement schemes as well as on fund a m e n t a l processes, n e w trends, a n d fusion reactor technology. A m o n g the low-beta systems particle c o n t a i n m e n t times in the n e i g h b o u r h o o d o f neoclassical values have been achieved in the W I I - b Stellarator at Garching. Also in the H e l i t r o n - D device at K y o t o University such c o n t a i n m e n t times have been observed. Successful results are further reported in connection with the E L M O b u m p y torus experiments at O a k Ridge where a highfrequency heated p l a s m a is stably confined in 24 m a g n e t i c m i r r o r sectors f o r m i n g a closed bottle. In a n u m b e r o f multipoles being operated at low p l a s m a densities, a n o m a l o u s losses have been observed at t e m p e r a t u r e s above the value c o r r e s p o n d i n g to the ionization energy. Several inertial confinement experiments are reported, being based on laser-driven as well as on electron b e a m - d r i v e n c o m pression. T h u s , c o m p r e s s i o n ratios up to 200 have been achieved in certain laser-driven processes u n d e r a high degree o f s y m -

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