Seminar INFLPR, Marti, 7 Februarie 2023, ora 10:00, Laborator FPFN, Dr. Florin Spineanu: The "Bootstrap Current" and its absence

Seminar INFLPR

Marti, 7 Februarie 2023, ora 10:00

Laborator FPFN

Titlu: The "Bootstrap Current" and its absence

Prezintă: Dr. Florin Spineanu

Sesiunile de lucru ale Teoriei Plasmei

Abstract: The “bootstrap” electric current is specific to the toroidal geometry and is highly precious for Tokamak plasma. It exists due to the collisional momentum exchange between the population of trapped particles (on banana orbits) and the circulating particles. We will show that a popular physical picture is not satisfactory and that a detailed presence of collisionality must be preserved even in the simplest descriptions. Since the inductive current has finite-time existence the bootstrap current (being an intrinsic effect) will take the charge of maintaining the magnetic field that supports the confinement. However the reactor with its very high temperature will have very low collisionality, which reduces the bootstrap current and sends the message that we must look for other sources of currents, if any.