“…Even though these methods produce satisfactory results with relatively few particles, for some applications (in particular, when particles in the tail of the distribution function play an important physical role, or when one wants to study the influence of density fluctuations which are at the origin of instabilities), it is well known that the numerical noise inherent in the particle methods becomes too significant. Consequently, methods which discretize the Vlasov equation on a phase space grid have been proposed (see (Feix et al, 1994;Filbet et al, 2001;Filbet and Sonnendrücker, 2003;Ghizzo et al, 1996;Ghizzo et al, 1990;Shoucri and Knorr, 1974; for plasma physics and (Bermejo, 1991;Staniforth and Coté, 1991) for other applications). Among these Eulerian methods, the semi-Lagrangian method consists in computing directly the distribution function on a Cartesian grid of the phase space.…”