An Object-Oriented Parallel Particle-in-Cell Code for Beam Dynamics Simulation in Linear Accelerators

We present an object-oriented three-dimensional parallel particle-in-cell (PIC) code for simulation of beam dynamics in linear accelerators (linacs). An important feature of this code is the use of split-operator methods to integrate single-particle magnetic optics techniques with parallel PIC techniques. By choosing a splitting scheme that separates the self-fields from the complicated externally applied fields, we are able to utilize a large step size and still retain high accuracy. The method employed is symplectic and can be generalized to arbitrarily high order accuracy if desired. A two-dimensional parallel domain decomposition approach is employed within a message-passing programming paradigm along with a dynamic load balancing scheme. Performance tests on an SGI/Cray T3E-900 and an SGI Origin 2000 show good scalability of the object-oriented code. We present, as an example, a simulation of high current beam transport in the accelerator production of tritium (APT) linac design.