ECR source scaling concepts

The main criteria for multiply charged ion production (i.e. for electron cyclotron resonance ion sources) are defined. Only the measurable parameters are considered: ω and P (the RF frequency and RF input power), B (the average magnetic confinement field), q (the ion charge), M (the ion mass), and I^q (the ion currents). All the usual but not directly measurable plasma characteristics are excluded, and only a few classical plasma rules about confinement and quiescence are included in the basic assumptions. They are then combined with ionization potentials and cross sections and result in the following scalings: q αlog ω^3.5, q αlog B ^1.5, qα P^1/3, and I^qα ω² M^-1. These relations suggest a soft upgrading by increasing ω, B, and P. Experiments confirm the tendencies to a certain extent and allow further extrapolations