Negative Ion Beams and Secondary Beams
The development of powerful negative ion sources requires precise and versatile simulation tools to predict the emittance of the extracted ion beams and the heat load on the electrodes. A first tool is a determination of the plasma beam interface which is accomplished by a set of macro based in the COMSOL Multiphysics environment. Notwithstanding the strong nonlinearities involved, a proper sequence of solver settings allows convergence to solution. Also a simple gas pressure model is included. A second tool consist in a database of atomic collision reactions that produce secondary ions. A third tool compute the secondary particle trajectories and the resulting heat load. As a final tool, the electrode temperature rise is simulated both with 2D an 3D COMSOL Multiphysics models.