Multi-turn injection into a heavy-ion synchrotron in the presence of space charge

TL;DR

This paper presents a detailed simulation model for multi-turn injection in heavy-ion synchrotrons, incorporating space charge effects to optimize beam injection efficiency and minimize beam loss.

Contribution

A comprehensive simulation model that includes space charge effects for optimizing multi-turn injection in heavy-ion synchrotrons.

Findings

Space charge causes tune shifts and phase space smoothing.

Optimized injection parameters reduce beam loss and vacuum degradation.

Simulation aligns with experimental observations.

Abstract

For heavy-ion synchrotrons an efficient Multi-Turn Injection (MTI) from the injector linac is crucial in order to reach the specified currents using the available machine acceptance. The beam loss during the MTI must not exceed the limits determined by machine protection and by the vacuum requirements. Especially for low energy and intermediate charge state ions, the beam loss at the injection septum can cause a degradation of the vacuum and a corresponding reduction of the beam lifetime. In order to optimize the injection of intense beams a very detailed simulation model was developed. Besides the closed orbit bump, lattice errors, the position of the septum and other aperture limiting components the transverse space charge force is included self-consistently. The space charge force causes a characteristic shift of the optimum tunes and a smoothing of the phase space density.