Quadrupole field geometries for intense electron beam acceleration

High-intensity electron beams could be focused in low-frequency RF accelerators and induction linear accelerators by adding transverse components to the accelerating electric field. Calculations with a 3D code show that quasielectrostatic focusing is sufficient to transport kiloampere electron beams in RF accelerators and the high-energy sections of induction accelerators. The elimination of conventional magnetic focusing systems could lead to reductions in the volume and weight of high-current electron accelerators. Two novel quadrupole geometries are investigated: a periodic array of spherical electrodes with alternating displacements and a set of plate electrodes with elliptical apertures.