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The plasma neutralizer (PN) could be an attractive upgrade for the Neutral Beam Injection (NBI) system of the International Thermonuclear Experimental Reactor (ITER). A multicusp magnetic trap with microwave discharge plasma generation was proposed as a scheme for PN.The experimental investigation of the scheme is undertaken in Kurchatov Institute.

Within the framework of the Adaptive Plasma Experiment (APEX) conceptual project, a trap with closed magnetic field lines, the Experimental Pseudo-Symmetric Closed Trap (EPSILON), is examined. The APEX project is aimed at theoretical and experimental development of the physical foundations for a steady state thermonuclear reactor designed on the basis of an alternative magnetic trap with tokamak-like large β plasma confinement. A discussion is given of the fundamental principle of pseudo-symmetry, which a magnetic configuration with tokamak-like plasma confinement should satisfy. Examples are given of calculations in the paraxial approximation of pseudo-symmetric curvilinear elements with a poloidal modulus B isoline. The EPSILON trap, consisting of two direct axisymmetric mirrors linked by two curvilinear pseudo-symmetric elements, is considered. To increase the equilibrium β, the plasma currents are short-circuited within curvilinear equilibrium elements. An untraditional scheme of MHD stabilization for a trap with closed field lines by use of axisymmetric mirrors with a divertor is analysed. The experimental installation EPSILON-One Mirror Element (OME), which is under construction for experimental investigation of stabilization by divertor, is discussed. The opportunity for applying the ECR method of plasma production in EPSILON-OME in conditions of high density and low magnetic field is examined.

Physical plasma method of separation by mass of the constituent elements together with chemical methods could find application in the fuel cycle of fast recators. These methods could also be useful for separating decay products during reprocessing of spent fuel of existing reactors and in the solution of questions concerning safety and nonproliferation. A possible plasma separation scheme is presented: solid-state material is transferred in a magnetic field into a low-temperature plasma flow and ions in a prescribed mass range are selectively accelerated and then spatially separated in a toroidal magnetic field.The problems of nuclear materials handling arise beause it is necessary to separate the initial material with a complicated composition into groups of elements in order to obtain products which are suitable for subsequent use or disposal. Ordinarily, this is accomplished by dissolving solid nuclear material and then separating the components. Radiochemical methods have their undoubted advantages and disadvantages, specifically, due to the formation of a large quantity of radioactive wastes when the spent fuel is reprocessed.The types of nuclear materials are diverse. They can be spent nuclear fuel or radioactive wastes. They can differ according to the degree of burnup, storage time, and technical state. Methods for handling these materials must take account of all their characteristics, be ecologically clean, and meet the requirements of the nonproliferation principle.The idea of using the plasma state of a material to develop a universal method for reprocessing wastes was advanced in the middle of the twentieth century. It was suggested that a thermal nuclear reactor be used for this [1]. Now, it is suggested that a low-temperature plasma be used for these purposes. Commercial reprocessing of toxic and other wastes by plasma methods is being considered [2]. Full-scale investigations of isotope separation by plasma methods have been performed [3]. The technological processes using low-temperature plasma have been developed and are used in the nuclear fuel cycle [4]. A plasma technology is proposed and used for reprocessing radioactive wastes [4,5].A long-term program for developing nuclear power requires the development of fast reactors with a solution of the problems of fuel balance, economics, and safety. Elimination of the isotopic separation of uranium and separation of plutonium from the uranium is a necessary condition for nuclear power to be proliferation resistant. In contrast to chemical methods, physical plasma separation methods without high resolution with respect to atomic mass can meet this condition.

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Receiving higher emphasis on the neutral beam ͑NB͒ off-axis current drive, the NB system is being highlighted for the steady state operation of the International Thermonuclear Experimental Reactor ͑ITER͒. To fulfill the physics requirement of heating and current drive, the NB system delivers ϳ50 MW of D 0 beams at 1 MeV into the ITER plasmas. The NB injector was designed so as to minimize the axial length, to avoid cost impact on the building. It was estimated by nuclear analyses that the insulation gas around the beam source would cause radiation induced conductivity, which would result in a power dissipation of Ͼ100 kW in the gas itself. As a result the present design utilizes vacuum insulation around the beam source. Since the vacuum pressure inside/outside the beam source ranges 10 Ϫ1 -10 Ϫ2 Pa, both gas ͑glow͒ and vacuum arc discharges are taken into account in the design.

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