title: Wall-loss distribution of charge breeding ions in an electron cyclotron resonance ion source.
abstract: The ion loss distribution in an electron cyclotron resonance ion source (ECRIS) was investigated to understand the element dependence of the charge breeding efficiency in an electron cyclotron resonance (ECR) charge breeder. The radioactive (111)In(1+) and (140)Xe(1+) ions (typical nonvolatile and volatile elements, respectively) were injected into the ECR charge breeder at the Tokai Radioactive Ion Accelerator Complex to breed their charge states. Their respective residual activities on the sidewall of the cylindrical plasma chamber of the source were measured after charge breeding as functions of the azimuthal angle and longitudinal position and two-dimensional distributions of ions lost during charge breeding in the ECRIS were obtained. These distributions had different azimuthal symmetries. The origins of these different azimuthal symmetries are qualitatively discussed by analyzing the differences and similarities in the observed wall-loss patterns. The implications for improving the charge breeding efficiencies of nonvolatile elements in ECR charge breeders are described. The similarities represent universal ion loss characteristics in an ECR charge breeder, which are different from the loss patterns of electrons on the ECRIS wall.
authors: High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.
authors: S C
authors: SC
authors: Jeong
authors: M
authors: M
authors: Oyaizu
authors: N
authors: N
authors: Imai
authors: Y
authors: Y
authors: Hirayama
authors: H
authors: H
authors: Ishiyama
authors: H
authors: H
authors: Miyatake
authors: K
authors: K
authors: Niki
authors: M
authors: M
authors: Okada
authors: Y X
authors: YX
authors: Watanabe
authors: Y
authors: Y
authors: Otokawa
authors: A
authors: A
authors: Osa
authors: S
authors: S
authors: Ichikawa