[en] Consideration is given to magnetic field stabilizer, designated for formation of magnetic well in closed plasma confinement magnetic systems with circular magnetic surfaces. The stabilizer is based on using quadrupole and hexapole fields, distributed along the rectilinear axis with homogeneous field, for displacement of magnetic axis of closed plasma confinement system

[en] Interchange instabilities in a plasma confined by a periodic magnetic mirror field are theoretically stabilized by a minimum-average-B well, which can be created by superposing a quadrupole field upon the mirror field. The arbitrary magnetic field is expanded to fourth power in radius and the depth and radial extent of the well are calculated. Variational and heuristic techniques are used to determine field shapes which optimize various well parameters. A simple, realistic coil geometry is given for a minimum-average-B well applicable to multiple mirror fusion reactors. The stabilization of interchange modes was investigated experimentally with a thermal lithium plasma confined by a periodic magnetic mirror field with adjustable curvature. As the destabilizing curvature was reduced, the transverse velocity of the m = 1 mode was observed to decrease substantially. The stabilization was greater than that predicted by curvature reduction alone; an explanation in terms of line-tying is presented. The stabilization of higher order modes by finite Larmor orbit effects was observed to be less than theoretically predicted; destabilization of the modes by incomplete line-tying is suggested

No abstract available

[en] Density fluctuations delta n/n < approximately 20%, were observed to have no effect on the classical diffusion of a collisional helium plasma across a poloidal octupole field with an additional weak toroidal field. The implication of these results on tokamak scattering experiments is discussed. (Auth.)

[en] A method of magnetic well formation in a closed system by inhomogeneity of magnetic surface ellipticity and the third magnetic field harmonics, is considered. An earlier proposed magnetic shape element with a direct magnetic axis and inhomogeneity indicated, convenient to be used for application of this method is investigated. Consideration is conducted taking a dragon type trap as an example

No abstract available

[en] Mirror device, connected with a high-curvature element (force line curvature radius is smaller, than the distance from the axis) of the opposite sign, is investigated. It is shown that in relatively axisymmetric configuration, including simple mirror device, flute stability is attainable according to the average minimum-B principle

[en] It is shown that an annular minimum of B is possible in a wide class of nonparaxial confinement systems, including the mirror and reversed field configurations

No abstract available

[en] The characteristics of the magnetic field and the length of the equilibrium section were determined in a curvilinear element (CREL) of the DRAKON fusion system. Experimental measurements of vacuum electron drift were performed by the drift shift method on the 'Geodesic CREL' facility, which consists of two periods of a five-period helical geodesic torus. The drift was found to be confined within an equilibrium section 1.5 periods long - a result that agrees with calculations. This CREL variant is topologically analogous to the theoretical model of a CREL known as '1.5 tori'. (author). Letter-to-the-editor. 5 refs, 7 figs