Multiple charge beam dynamics in Alternate Phase Focusing structure

TL;DR

This paper demonstrates the use of an asymmetrical alternate phase focusing (A-APF) structure with superconducting resonators to accelerate multiple charge states of uranium ions efficiently, highlighting its potential for advanced ion beam applications.

Contribution

It introduces a novel A-APF focusing scheme that enables simultaneous acceleration of multiple charge states in superconducting resonators, optimizing phase tuning and solenoid fields.

Findings

81% of uranium beam accelerated to 6.2 MeV/u

Simultaneous acceleration of 10 charge states from 34+ to 43+

Mitigation of steering effects through phase and field optimization

Abstract

Asymmetrical Alternate Phase (A-APF) focusing realized in a sequence of 36 Superconducting Quarter Wave Resonators has been shown to accelerate almost 81 % of input Uranium beam before foil stripper to an energy of 6.2 MeV/u from 1.3 MeV/u. Ten charge states from 34+ to 43+ could be simultaneously accelerated with the phase of resonators tuned for 34+. A-APF structure showed unique nature of large potential bucket for charge states higher than that of tuned one. Steering inherent to QWRs can be mitigated by selecting appropriate phase variation of the APF periods and optimization of solenoid field strengths placed in each of the periods. This mitigation facilitates multiple charge state acceleration scheme