摘要 |
The present invention provides an accelerating structure capable of increasing a degree of vacuum at a middle part inside the accelerating structure while confining an alternating electric field to the inside. An accelerating structure 1 is formed of a plurality of annular discs 2 and 3 serially connected into a cylindrical shape. At least one of the discs 3 disposed at a middle part of the accelerating structure 1 includes: a choke structure formed by a choke filter 7; and a vacuum port 8 opened in an outer circumferential surface of the disc further on an outer circumferential side than the choke structure, and the vacuum port 8 is connected to an external exhaust device. |