Scientific seminar “On two-stream instability of states of dynamic equilibrium of a Vlasov-Poisson plasma”
14 December at 12:00 MSK
We study the problem of linear stability of one-dimensional states of dynamic equilibrium of an infinite collisionless electrically neutral plasma in the electrostatic approximation - Vlasov-Poisson plasma. It was proved by the direct Lyapunov method that these equilibrium states are absolutely unstable with respect to one-dimensional small perturbations in the case when the Vlasov-Poisson plasma contains electrons and a single type of ions with stationary distribution functions isotropic in physical space, but variable in the velocity continuum.
Sufficient conditions for linear practical instability are obtained, an a priori exponential lower estimate is constructed, and the initial data for small perturbations growing in time are described. An illustrative analytical example of the considered one-dimensional states of dynamic equilibrium and small perturbations of the same symmetry superimposed on them, which grow in time in accordance with the constructed estimate, are constructed.
Professor Gubarev Yuri G. (NSU, Novosibirsk).