Time Domain Wake Field Computation With Boundary Element Method

Abstract—We describe and demonstrate a time-domain boundary-element method for numerical computation of wake fields. The accelerator structure is modeled with a surface mesh, and the wake field is easily split from the self fields of the source particles. The formulation for three-dimensional structures is introduced first, followed by two formulations for axisymmetric structures. We briefly describe methods for computing the wake potential in a boundary-element code. Finally, we compare the fully axisymmetric formulation with codes based on the finite integration technique (FIT). The other two formulations are demonstrated with modest examples. Index Terms—Boundary element method (BEM), electric field integral equation (EFIE), magnetic field integral equation (MFIE), wake fields, wake potentials. I