Patent ID: 8772733

Claim:
A charged particle accelerator that accelerates a charged particle beam to be irradiated onto an irradiation subject by a particle beam irradiation apparatus, the charged particle accelerator comprising: a vacuum duct through which the charged particle beam passes; an acceleration cavity that accelerates the charged particle beam passing through the vacuum duct; a deflection electromagnet that deflects the charged particle beam passing through the vacuum duct; and an accelerator control apparatus that controls the acceleration cavity and the deflection electromagnet, wherein the accelerator control apparatus includes a clock generation unit that generates an acceleration cavity clock and an electromagnet clock that is synchronized with the acceleration cavity clock and has a frequency lower than the frequency of the acceleration cavity clock; a high-frequency control unit that controls the acceleration cavity, based on an acceleration cavity pattern stored in a first pattern memory and the acceleration cavity clock; and a deflection electromagnet control unit that controls the deflection electromagnet, based on a deflection electromagnet pattern stored in a second pattern memory and the electromagnet clock.