Charge Breeding of Radioactive Ions

TL;DR

Charge breeding enhances the charge state of radioactive ions through various methods, enabling their use in advanced experiments and accelerators, with detailed discussion of physics, techniques, and practical considerations.

Contribution

This paper provides a comprehensive overview of charge breeding techniques for radioactive ions, including physics processes, methods, and practical beam delivery aspects.

Findings

Analysis of physics processes in charge breeding

Comparison of three main charge-breeding methods

Discussion of beam parameters and practical devices

Abstract

Charge breeding is a technique to increase the charge state of ions, in many cases radioactive ions. The singly charged radioactive ions, produced in an isotope separator on-line facility, and extracted with a low kinetic energy of some tens of keV, are injected into a charge breeder, where the charge state is increased to Q. The transformed ions are either directed towards a dedicated experiment requiring highly charged ions, or post-accelerated to higher beam energies. In this paper the physics processes involved in the production of highly charged ions will be introduced, and the injection and extraction beam parameters of the charge breeder defined. A description of the three main charge-breeding methods is given, namely: electron stripping in gas jet or foil; external ion injection into an electron-beam ion source/trap (EBIS/T); and external ion injection into an electron cyclotron resonance ion source (ECRIS). In addition, some preparatory devices for charge breeding and practical beam delivery aspects will be covered.