Raphael Gutser
Experiments and Simulations for the Dynamics of Cesium in Negative Hydrogen Ion Sources for ITER N-NBI
Supervisor: apl. Prof. Dr.-Ing. Ursel Fantz [Experimental plasma physics]
Date of oral examination: 07/21/2010
189 pages, english
The injection of fast neutral beams (NBI) into a magnetically confined fusion plasma is an important method for plasma heating and current drive. The NBI for the future ITER experiment will require 1 MeV D neutral beams, generated by the acceleration and neutralization of negative ions from an RF-driven ion source. These ions are converted from plasma particles on a cesium covered surface. The optimization of the dynamics and spatial distribution of cesium within the ion source is therefore of high importance. Within the scope of this thesis, the Monte Carlo based numerical transport simulation CsFlow3D was developed, which is the first computer model that is capable of simulating the flux and the accumulation of cesium on the surfaces of negative-ion sources. Basic studies that support the code development were performed at a dedicated experiment at the University of Augsburg.