PHASE SPACE BOUNDARY INTEGRA-Vlasov plasmasa problem of great importance in both TION thermonuclear fusion research and astrophysics. In the past, only limited progress has been achieved in this direction, due Catalogue number: ABVU to the complexity of the problem. Program obtainable from: CPC Program Library, Queen's Method of solution University of Belfast, N. Ireland (see application form in this When the distribution function f(x, v, t) of a collisionless issue) plasma is pictured as the density ofan incompressible "phase fluid" moving in the two dimensional (x, v) phase space, by Computer: CDC 6600; Installation: Tel Aviv University, Liouville theorem, it is sufficient to follow the motion of the Israel boundary curve(s) which enclose regions ofconstantfin phase space in order to know the state of the system. Thus, Operating system: Scope 3.3 it is possible to investigate a system consisting of a very large number of particles (enclosed by a boundary curve) without Programming language: FORTRAN having to treat them explicitly. The method was first used by Roberts and Berk [1] for plasma systems~It has been further High speed store required: CM 150 000 words developed by Cuperman et al. [2] for gravitational systems. This paper describes the adaptation (transformation) of the No. of bits of word: 60 improved phase-space boundary integration code of Cuperman et al. [2] to the plasma case. Overlay structure: none Restriction on the complexity of the problem No. of magnetic tapes required: two The code may be used only for the investigation of onedimensional (two-dimensional phase space), collisionless Other peripherals used: line printer plasma systems consisting of regions of constant density (in phase space). No. of cards in combined program and test deck: 1450 Typical running time Card punching code: CDC 63 -character set 26
Execution times depend on the number of Eulerian strips used and on the number of mark pointsrequired to describe Keywords: plasma physics, nonhomogeneous Vlasov systems, the system with the desired accuracy. Typically, if the numwater bag plasmas ber of Eulerian strips used is 215, the execution time per time step for one mark point is about 1.5 X iO~s.
Nature of the physical problem
We consider the nonlinear evolution of nonhomogeneous References