SEPTUM ELECTROMAGNET AND PARTICLE BEAM THERAPY DEVICE

摘要

A septum magnet includes a yoke (1) that is arc-shaped, that has a gap portion (1s) opening at the outer circumference side thereof and extending in a circumferential direction thereof, and that can be separated at the approximately center portion thereof in the axis direction; a septum coil (3) that is provided inside the gap portion (1s) but at the outer side thereof in the radial direction and in which an electric current flows in one direction in the circumferential direction; a return coil (4) that is provided in such a way as to be at the inner side of the gap portion (1s) in the radial direction and to face the septum coil (3) with a predetermined distance, and in which an electric current flows in opposite direction to that of the electric current in the septum coil (3); and a vacuum duct (2) that is inserted between the septum coil (3) and the return coil (4). The septum coil (3) is formed in such a way as to be able to be separated into a first portion (3u) and a second portion (3d) in response to separation of the yoke (1); and in a space between the septum coil (3) and the vacuum duct (2), there is provided an auxiliary coil (5), in two portions of which, corresponding to the first portion (3u) and the second portion (3d) of the septum coil (3), electric currents flow in opposite direction to each other in the circumferential direction.