An exact particle splitting algorithm for PIC codes

Abstract

Splitting and merging are long standing issues in PIC codes. I propose a novel algorithm devoted to exact splitting for Particle-In-Cell (PIC) codes relying on Adaptive Mesh Refinement (AMR) grids. AMR grids have - by definition - a constant refinement factor between levels, this strong property combined with B-spline shape functions makes possible exact splitting of macro-particles in space. The proposed exact splitting method is applicable for any integer refinement factor and B-spline shape functions of arbitrary order. Besides, this exact algorithm removes by construction the usual numerical noise increase resulting from approximate particle splitting strategies.