Magnet for ion beam irradiation apparatus equipped with protective member that covers plurality of magnetic field concentrating members

摘要

A magnet used in an ion beam irradiation apparatus includes a pair of magnetic poles arranged facing each other on an inner side of the magnet across an ion beam; a plurality of magnetic field concentrating members that are arranged on each of the opposing surfaces of the magnetic poles and that perform a function of trapping electrons between the magnetic poles; and a protective member that covers opposing surfaces of the magnetic field concentrating members.