QPT, a simple particle tracker for tube simulation

Today, numerical simulations are an inherent part of the design process of electron vacuum tubes. By now, a number of PIC codes have been developed which allow for the simulation of complete electron tubes. However, due to their long calculation times these codes are not a good choice at the beginning of a design process or for the quick inspection of a new idea. Moreover, there are a lot of structures which can only be adequately modeled by a very fine mesh, resulting in an extremely small time step and therefore in an inconvienent simulation time. The particle tracker presented in this paper shows, that there is not always the need for an expensive high performance code or a large computer cluster. For a lot of problems, satisfying results can be achieved much faster by a simple code.