2D and 3D Simulation of Ion Beam Extraction from the ECR Ion Source

Spaedtke P., Tinschert K.
Gesellschaft fuer Schwerionenforschung mbH, Planckstrasse 1, D-64291 Darmstadt, Germany

The ion beam extraction from an ECR source is affected by many parameters as: geometry and applied potentials, magnetic flux density distribution including the hexapole contribution, space charge of the extracted beam and the shape of the plasma boundary. This plasma boundary itself is determined by plasma density, the extraction field strength and the electron temperature distribution of slow electrons.

A 2D-simulation of the electrostatic potentials including the space charge and the corresponding ion trajectories was used to compare our experimental results for two different extraction geometries.

The fact that the ion density distribution within the plasma is influenced by the magnetic multipole distribution originating from the magnetic hexapole field requires a 3D-simulation.

In all cases the experimentaly obtained charge state distribution was used as input for the simulation. This simulation was made for the dc and the afterglow mode.

Presenting Author : Spaedtke P.
Presentation : Oral
Wednesday 10:00