Conceptual design of a helicon ion source for high-current dc accelerators

Abstract

Characteristics of helicon plasmas are examined as a candidate for accelerator ion sources. Helicon plasmas have much higher density with very high power efficiency in a relatively lower magnetic field than electron cyclotron resonance plasmas do. High electron density and high electron temperature are beneficial to extract high ion current density. Low magnetic field favors for low-emittance accelerators. Taking advantage of placing antenna outside of the plasma chamber, source contamination can be kept low enough to maintain a stable operation for longer periods. Based on these characteristics, new designs of high current ion sources using helicon waves are proposed for accelerator applications for the first time.