Improved ion production and extraction on tandem type ECRIS with low magnetic mirror field

Abstract

A tandem-type electron cyclotron resonance (ECR) ion source (ECRIS) has been constructed for synthesizing, extracting, and analyzing ions. The feasibility and realization of the device which has rangy operation window in a single device are investigated to produce many kinds of ion beams like universal source based on ECRIS. The ECR plasmas are considered to be necessary to be available to coexist and to be operated individually with different plasma parameters. Both of analysis of ion beams and investigation of plasma parameters will be conducted on produced plasmas. In this article the experimental study concentrates on improvement of producing and extracting multicharged ion beams from the second stage of the tandem-type ECRIS under lower magnetic mirror field with octupole magnets. The assembly of the extractor is modified and their positions, gap, and potentials are investigated against each ion spices. We succeeded in producing, extracting multicharged ion currents and improving ion extraction, while the magnetic field is about 60% of the previous magnetic field strength. We will present obtained evidences experimentally in detail.