Uniform transverse beam profile with a new type nonlinear magnet

Abstract

In this paper, a new type magnet is proposed and processed to uniform the transverse beam profile. Compeared to the octupole, the new type magnet can prove a similar octupole magnet field in the middle, but the rise rate declines quickly in the edge. So that, a same uniform beam is got with less particles loss. Besides that, a mechanical structure is added to adjust the width of the middle region to satisfy different transverse dimensions, and this whould further reduce particles loss. Some numerical simulations have been done respectively with the octupole and the new type of magnet to show the advantages of the new type magnet.