Design of an electron cyclotron resonance ion source for the isotope separator and accelerator at TRIUMF

Abstract

A 2.45 GHz electron cyclotron resonance ion source has been designed and built to ionize radioactive atoms and produce single charged ion beams for the isotope separator and accelerator at TRIUMF. The source is characterized by its short axial length (8 cm) and the small pair of magnetic coils (diam=φ26 cm) placed adjacent to the source cavity. A small diameter quartz tube is inserted in the cavity to confine the plasma to a small volume and to shorten total ion transient time for the exotic gaseous elements with short and intermediate half life. The computer code POISSON is used to design the magnetic coils. A three-electrode extraction system simulated with the code IGUNE is used to study the beam extraction efficiency. In this article the design of the source, extraction system, and the preliminary results on beam emittance and energy spread are presented; the results on ion transient time, ionization efficiency, and beam extraction efficiency are presented in a separate article.