Concept for a fourth generation electron cyclotron resonance ion source.

A fourth generation electron cyclotron resonance ion source with an operating frequency between 40 and 56 GHz has the potential to quadruple the heavy-ion beam currents and provide a cost effective upgrade path for heavy ion drivers in use or in the planning stage at radioactive beam facilities. Design studies show it is feasible to produce the required magnetic fields in the plasma chamber, 7 T axially and 4 T in the radial direction with a magnetic structure using commercially available Nb(3)Sn superconducting materials. In this paper we describe the design of such a magnet structure including a 3D analysis of the Lorentz forces generated by the magnetic fields and the necessary clamping structure to stabilize the conductor against these forces.