Optimization of mass separators

Abstract

The optimization of separator masses in this paper is based on the realization of the linearity of the system under study and the consequences of Liouville's theorem. The properties of several mass separators with an ion energy of 30 keV and a beam emittance of 4 mm·mrad are considered. Focusing is provided by an aberration-free lens and a magnetic corrector. Phase diagrams along the beam path are in the form of parallelograms, which indicates the absence of geometric aberrations. For each of the separators, the resolution calculated in the linear approximation coincides with the simulation results. It is shown that a mass separator based on a magnet with a rotation angle of 54.7o has a resolution of about 5000, and a separator based on two magnets with a rotation angle of 45o and 90o, respectively, has a resolution of 14 000-15 000. Keywords: ion optics, emittance, lenses, phase diagram, aberrations.