No abstract available

[en] A simple class of static equilibria, in the ideally conducting magnetohydrodynamic approximation, is found to include linear systems having surfaces of constant hydrodynamic pressure with a cylindrical topology and elliptic transverse cross-section functionally dependent on an axial co-ordinate. These suggest a possible mode of behaviour for non-axisymmetric toroidal systems and might themselves be realized experimentally as free boundary configurations of a plasma in an applied quadrupole-like magnetic field. (author)

[en] A special coordinate system based on the work of H. Ono and A. Tsuro has been used to derive exact semi-analytic formulas for the flux from cylindrical, spherical, toroidal, rectangular, annular and truncated cone volume sources; from cylindrical, spherical, truncated cone, disk and rectangular surface sources; and from curved and tilted line sources. In most of the cases where the source is curved, shields of the same curvature are allowed in addition to the standard slab shields; cylindrical shields are also allowed in the rectangular volume source flux formula. An especially complete treatment of a cylindrical volume source is given, in which dose points may be arbitrarily located both within and outside the source, and a finite cylindrical shield may be considered. Detector points may also be specified as lying within spherical and annular source volumes. The integral functions encountered in these formulas require at most two-dimensional numeric integration in order to evaluate the flux values. The classic flux formulas involving only slab shields and slab, disk, line, sphere and truncated cone sources become some of the many special cases which are given in addition to the more general formulas mentioned above

[en] A multipole magnetic well for plasma confinement includes a plurality of current-carrying coils placed on planes corresponding to the facets of a regular polyhedron that can be symmetrically circumscribed about a sphere. The direction of current in the coils is such as to minimize the flux density at the center of the polyhedron, thereby providing a confinement well with three-dimensional symmetry having an increasing flux density in all directions from the center. 16 claims, 18 figures

[en] Calculations are presented which show the effects of magnetic field perturbations on toroidal multipole fields used for plasma confinement. The field topology was destroyed, with the attendant formation of magnetic surfaces. In contrast to earlier calculations, exact equations are solved numerically and the results apply to actual experiments in which the plasma lifetime was seriously decreased by the perturbing field

No abstract available

[en] The present work continues our previous paper in which all possible triangulations of the plane using three pencils of circles were listed. In the present article we find all projectively distinct triangulations of the plane by pencils of conics that are obtained by projecting regular three-webs, cut out on a nondegenerate cubic surface by three pencils of planes, whose axes lie on this surface. Bibliography: 6 titles

[en] Calculation of Wilson Loops (WL) to second order, are performed for different shapes of the path, using dimensional regularization techniques. Some useful formulae are developed. In particular a discussion is given on the influence of points of contact, cusps and intersections, on the residue of the resultant pole. For smooth curves WLs are finite. (Author)

[en] The achievement of field reversal is shown not to ensure a closed magnetic geometry. The closure of the reversed field geometry is found to be critically dependent on the shape of the toroidal component of the magnetic field no matter how small it may be

[en] Calculation of a particles flux, emitted by an isotropic point source through a plane surface and application to a cylindrical radiometer. This article establishes the expression of particle flux, emitted in the vacuum by an isotropic point source through a plane surface. The equation is then compared with numerical results obtained in some examples by using symmetries. An application is proposed for a cylindrical detector (non-planar surface). Complements are given in conclusion. (author)