Seminar INFLPR, Joi, 9 Martie 2023, ora 10:00, Laborator FPFN, Dr. Florin Spineanu: Equations of motion of particles in strong magnetic field
INFLPR Seminar
Thursday, 9 March 2023, 10:00 am
PPNF Laboratory
Title: Equations of motion of particles in strong magnetic field
Lecturer: Dr. Florin Spineanu
Work Sessions of Plasma Theory
Abstract: To obtain the magnitude of physical quantities of practical interest in plasma research (fluxes, statistical averages, etc.) one needs the distribution function, a functional of the system's state. For a wide range of plasma systems the distribution function for a population of particles (electrons, ions, impurities) can be described by the Fokker Planck equation, derived from most general conservation principle (Liouville equation). To solve the Fokker Planck equation one needs the trajectories of the particles. The latter can be obtained by solving the equations of motion of particles in the particular configuration of fields.
We will define the configuration of geometry and fields that is appropriate to magnetic confinement (toroidal) but also to astrophysics and ionosphere. We will identify invariants of motion and write the equations of motion. We will show how the solutions are obtained analytically. The results can be simple and intuitive (allowing further euristic, qualitative, developments) and can be complex formulas that explore deeper details.
We will just draw attention to the boundaries separating this approach from neighbor research methods: PIC (particle in cell – simulations) Monte Carlo method for the test particle in turbulent fields.
As promised, we will also clarify few technical aspects of the previous subject ("Bootstrap current").
The raw text for this subject is 008_particle_equations_of_motion.pdf (free.fr) (explicitely http://florin.spineanu.free.fr/discussions/worksessions/008_particle_equ... )
The previous subject has an update 019_bootstrap.pdf (free.fr)
[a very short reference will be made to the hottest, most recent, result in fusion, the suppression of tungsten ions contamination by creating a huge temperature gradient at the edge]
Please send questions to florin.spineanu@gmail.com