3D axisymmetric space charge simulation via boundary elements and emitted particles

In many cases of field emission involving lower levels of current, the attenuating affects of space charge are minor. In such cases the boundary element (or ´charge density´) method is effective for computation of the relevant potentials and currents. This paper presents an attempt to combine the boundary element method for potentials with a scheme for particle launching and tracking in order to simulate space charge effects. As a measure of accuracy, the method developed is applied to the case of concentric spheres where numerical results can also be obtained by treatment as a 1-dimensional potential. Finally the method is applied to a laboratory situation.