No abstract available

[en] The author describes the caracteristics of fusion reactions and the operating conditions of a reactor using this type of energy source. Then follows an analysis of the key questions facing research workers in the fusion field: the physics of plasma formation

No abstract available

[en] After describing the Tokamak configuration concept, the author provides an analysis of the principal physical aspects of this type of installation and concludes by estimating that the Tokamak concept is a 'plausible candidate' as a means of producing controlled thermonuclear fusion

[en] A plasma generator comprises a discharge chamber provided with a means for introducing a plasma-forming medium and associated with a cathode assembly and an anode assembly. The latter includes at least two plasmatrons each having a hole for an inlet for the plasma-forming medium and being provided with an end electrode and an auxiliary hollow electrode. These electrodes are connected to an arc discharge initiating system. The exit openings of the auxiliary electrodes communicate with the discharge chamber and are evenly distributed along the perimeter of its cross section. The cathode assembly comprises at least two plasmatrons each having an inlet for the plasma-forming medium and being provided with an end electrode and an auxiliary hollow electrode. Both electrodes are connected to an arc discharge initiating system. In addition, the end electrodes are connected to the power supply. The exit openings of the auxiliary electrodes communicate with the discharge chamber and are evenly distributed along the perimeter of its cross section. The diameter of each exit opening of the auxiliary electrode of each plasmatron of each assembly, both cathode and anode, is selected to satisfy a specific relationship

[en] The preionization is discussed in Alvand IIC tokamak. Various preionization methods have been examined. It was found that the preionization has a strong influence on the formation and equilibrium of Alvand IIC tokamak plasmas. Carelessly handling of it leads to either not formation or delayed formation of plasma and causes a great deal of preliminary energy loss. Although a high frequency induced electric field makes a suitable preionization at high energies but creates noises in controlling and diagnostic systems and spoils their operation. Electron beam injection by means of an electron gun, makes sufficient preionization in high Zeff, if the beam flow direction is chosen correctly, but in low Zeff it fails in not so low beam energies. However, it has found that an arc discharge between two electrodes installed in limiter shadow, creates a suitable preionization if it is arranged correctly. We have used the secondary of a pulse transformer with a very low turns' ratio of secondary to primary to feed the electrodes

[en] Recent results on a crowbar method utilizing shock waves reflected by a pressure driven schock tube are presented. This crowbar technique could be used for plasma production

[en] A new method for creating high-current plasma channels is developed. The method uses a narrow gas column formed by the leading particles of a nonsteady gas jet outflowing into a vacuum. An electric discharge device with a system for the formation of a narrow gas column is experimentally studied. The parameters of emission from the plasma channel are measured

No abstract available

[en] For plasma production in fusion reactors a large amount of energy is needed to obtain the necessary plasma temperatures. More recently a method has been developed to deliver this energy by rf-power pulses up to more than 1 MW and a pulse duration of several seconds, which are produced in Klystrons. Here the Klystron TH2086 is described which has been developed by Thomson-CSF in cooperation with the French Atomic Energy Agency CEA. The different problems arising in the development of a suitable klystron are discussed, in particular efficiency, operation, and tuning considerations. Experimental results are presented. (ZDE)