Focusing method of elliptical sheet beam

In this paper, space-charge field distribution of elliptical sheet beam is derived. Then its Diocotron instability is observed using 3D PIC program. After that, transmission characteristics of the elliptical sheet beam transporting in periodical cusped magnet and offset-periodical cusped magnet are analyzed and simulated. Through comparison, it is concluded that offset-periodical cusped magnet is more suitable for restraining the Diocotron instability.