Study of the beam meander at JAERI cyclotron

Agematsu, Takashi; Fukuda, Mitsuhiro; Nakamura, Yoshiteru; Ishibori, Ikuo; Nara, Takayuki; Okumura, Susumu; Kurashima, Satoshi; Miyawaki, Nobumasa; Yoshida, Kenichi; Arakawa, Kazuo; Tajima, Satoshi

On JAERI cyclotron, it is needed to study the problem that is the meander of the beam envelope along the micro-beam line and the other beam lines. The causes of the meander mainly come from that the position and direction of the beam are not alignment with designed beam trajectory. We evaluated the beam meander at HZ line. The verticaly 3mm beam shift at the cyclotron exit is amplified to 60mm at the beam line. This cause of beam shift comes from the level down of several magnets near the cyclotron, we corrected already. For improvement of the beam meander on the horizontal plane, we installed the steering magnet. Roughly we could correct the beam meander. Although there are slightly the beam meander. We will study more about this problem.