Simulation on Buildup of Electron Cloud in Proton Circular Accelerator

TL;DR

This paper presents a simulation code to model the buildup, distribution, and density of electron clouds in a high-energy proton accelerator, addressing their impact on beam stability and loss.

Contribution

A new simulation tool specifically designed for the CSNS/RCS accelerator to study electron cloud formation and its effects on beam stability.

Findings

Simulation code effectively models electron cloud buildup in CSNS/RCS

Results indicate potential for electron cloud-induced beam instability

Insights aid in designing mitigation strategies for electron cloud effects

Abstract

Electron cloud interaction with high energy positive beam are believed responsible for various undesirable effects such as vacuum degradation, collective beam instability and even beam loss in high power proton circular accelerator. An important uncertainty in predicting electron cloud instability lies in the detail processes on the generation and accumulation of the electron cloud. The simulation on the build-up of electron cloud is necessary to further studies on beam instability caused by electron cloud. China Spallation Neutron Source (CSNS) is the largest scientific project in building, whose accelerator complex includes two main parts: an H- linac and a rapid cycling synchrotron (RCS). The RCS accumulates the 80Mev proton beam and accelerates it to 1.6GeV with a repetition rate 25Hz. During the beam injection with lower energy, the emerging electron cloud may cause a serious instability and beam loss on the vacuum pipe. A simulation code has been developed to simulate the build-up, distribution and density of electron cloud in CSNS/RCS.