Kube, Ralph

The topic of my dissertation are investigations of turbulent motions and fluctuation-driven transport in the edge region of magnetically confined plasmas. Since early fusion experiments, one universally observes high fluctuations in the edge region of magnetically confined plasmas. In the outermost region of the confined plasma, the scrape-off layer (SOL), where magnetic field lines intersect material surfaces, these fluctuations are accompanied by large transport events. Progress in experimental techniques and theoretical modeling allowed to link these transport events to the motions of plasma filaments which are elongated along the magnetic field lines and localized in the drift-plane perpendicular to the magnetic field.

The filaments contain excess particle density and heat which is transported outwards towards the vessel walls and material surfaces. This leads to an increased plasma flux to the main chamber wall and poses significant problems to the steady-state operation of fusion plasma experiments, including main chamber recycling, material mitigation and disruptions that lead to a sudden loss of plasma confinement. For a better qualitative understanding of these effects, dynamic properties of isolated plasma filaments are of great interest for the fusion community.