Abstract of HIMAT Project

The parallel particle-in-cell code EUTERPE consists of a particle part which scales very well and a field solver part which is much more intensive in communication. It prevents the PIC code to scale to thousands of cores. Thus, every improvement in the efficiency of the field solver part will significantly improve the scalability of the whole code. Within the last decade solver packages based on hierarchical (H-) matrices have been developed. For a finite element discretization H-matrices seem to efficiently approximate the Cholesky factorization which can be used either as a preconditioner for an iterative solver or as a direct solver. Especially for the three-dimensional stellarator geometry of EUTERPE this seems to be a good alternative as direct solvers usually are not applicable due to excessive memory consumption. Different publicly available implementations of H-matrix packages should be assessed on their impact to the solver part of the EUTERPE code.