IRRADIATION NOZZLE, PARTICLE THERAPY APPARATUS, PARTICLE THERAPY SYSTEM, AND METHOD FOR CONTROLLING PARTICLE THERAPY SYSTEM

To implement downsizing of an apparatus and highly accurate beam irradiation. An irradiation nozzle 4 that irradiates a target object Pt with a radiotherapy beam includes: a nozzle base part 42 fixed on a beam axis 40 through which the radiotherapy beam passes; and a nozzle tip part that irradiates the target object with the radiotherapy beam that has passed through the nozzle base part, in which the nozzle tip part is fixed at a first position when the target object is irradiated with the radiotherapy beam and is fixed at a second position when the target object is imaged, and a curved movement path in which the nozzle tip part is movable between the first position and the second position is provided.