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.
The main results are published in the following works:
- Gubarev Yu.G. Two-flow instability of particular class of one-dimensional dynamic equilibrium states of Vlasov-Poisson plasma // Plasma Res. Express. 2019. Vol. 1.No. 4. P. 045008-1 - 045008-13;
- Gubarev Yu.G. On Two-Flow Instability of Dynamical Equilibrium States of Vlasov-Poisson Plasma // In: Continuum Mechanics, Applied Mathematics and Scientific Computing: Godunov’s Legacy. A Liber Amicorum to Professor Godunov / Eds Gennadii V. Demidenko, Evgeniy Romenski, Eleuterio Toro, and Michael Dumbser. Chapter 21. Cham: Springer Nature Switzerland AG, 2020. P. 161-167 (ISBN 978-3-030-38870-6 (eBook)).
Speaker
Professor Gubarev Yuri G. (NSU, Novosibirsk).