A rotating capacitor is used in a circular accelerator that accelerates a charged particle beam by feeding a first radio frequency to a DC main magnetic field. The rotating capacitor modulates a frequency of the first radio frequency. The rotating capacitor includes a stator electrode and a rotor electrode used for modulating the frequency of the first radio frequency together with the stator electrode. A vacuum seal performs vacuum sealing around a shaft for rotating the rotor electrode. A bearing that supports the shaft is installed on an atmosphere side.

A radiation treatment session is initiated to deliver a therapeutic radiation beam from a therapeutic radiation source to a target. One or more X-ray radiation sources are caused to deliver an imaging radiation beam from the one or more X-ray radiation sources through the target to one or more X-ray detectors to acquire imaging data associated with the target during therapeutic radiation beam delivery. One or more volumetric images are constructed using the acquired imaging data.

Disclosed a particle accelerator that accelerates a charged particle beam while circulating the charged particle beam as a circulating beam and outputs some of the circulating beam as an output beam, the particle accelerator including: a first deflection section and a second deflection sections each having a deflection electromagnet; a first straight section, a second straight section, and third straight section each not having the deflection electromagnet; and a control unit, wherein a preceding output deflector of the first straight section deflects some of the circulating beam toward an inner side of a circulating trajectory of the circulating beam to separate the some of the circulating beam as an output beam, wherein a succeeding output deflector of the third straight section deflects the output beam separated from the circulating beam by the preceding output deflector toward an outer side of the circulating trajectory of the circulating beam, and wherein the control unit controls at least the quadrupole electromagnet such that a phase advance of a betatron oscillation of the output beam is 270±45 degrees in a section from the preceding output deflector to the succeeding output deflector.

Provided is a technique by which each nuclide is optimized in terms of energy and number of particles and pre-accelerated so as to be injected into a main accelerator in charged particle beam irradiation by the combined use of different nuclides.

A charged particle beam injector includes: a first ion source that generates first nuclide ions; a first linear accelerator that linearly accelerates the generated first nuclide ions to form a first charged particle beam; a second ion source that generates second nuclide ions; a second linear accelerator that linearly accelerates the generated second nuclide ions to form a second charged particle beam; and a switching electromagnet that injects one of the first charged particle beam and the second charged particle beam into an inflector of a main accelerator.

A photon source emits a flattening filter-free photon beam. A control circuit operably couples to a multi-layer multi-leaf collimator that is disposed between the photon source and a treatment area of a patient. The control circuit automatically arranges operation of some, but not all, of the layers of the multi-layer multi-leaf collimator to serve as a virtual flattening filter with respect to the flattening filter-free photon beam emitted by the photon source. By one approach, another of the layers of the multi-layer multi-leaf collimator serves to form a treatment aperture corresponding to a shape of the treatment area of the patient. By one approach the control circuit comprises an integral part of a treatment platform (as versus a dedicated treatment planning platform) and can carry out most or even essentially all of the planning steps that lead to administration of the treatment to a patient.

A radiation delivery system that includes a gantry to extend along one or more axes. The gantry is to provide a continuous rotation. The radiation delivery system includes a linear accelerator (LINAC) coupled to the gantry. The LINAC is to generate a treatment beam. The radiation delivery system includes a rotary joint coupled to the gantry. The rotary joint provides a physical connection from the LINAC to an external system that is positioned off the gantry. The physical connection is to transport radio frequency (RF) power.

A method of assisting designing of a particle beam therapy facility includes: a local-concave region calculation step of calculating a volume of a local concave region which is a concave region between two treatment-room models arranged most adjacent to each other, among multiple treatment-room models arranged in a model space corresponding to a target space for arrangement, or a projected area of the local concave region; a concave-region calculation-result display step of displaying the volume or the projected area of the local concave region calculated in the local-concave region calculation step, on a display device of a design assisting device; and a treatment-room model displacement step of displacing the treatment-room model in the model space in response to a displacement instruction for that treatment-room model, when no operation-termination instruction is issued after the concave-region calculation-result display step; wherein the above three steps are repeated until an operation-termination instruction is issued.

A particle radiation therapy apparatus 10 includes: a bed 15 for positioning of a patient 12; irradiation ports 16 (16a, 16b) that output a particle beam in a treatment room 11; a horizontal-direction imaging unit 21 composed of a first X-ray source 25 and a first X-ray detector 26 that face each other with the bed 15 interposed therebetween; a vertical-direction imaging unit 22 composed of a second X-ray source 27 and a second X-ray detector 28 that face each other with the bed 15 interposed therebetween; a storage room 18 for housing the first X-ray detector 26 under the floor when the horizontal-direction imaging unit 21 is not used; and a support member 23 that moves the first X-ray detector 26 above the floor and supports it between the bed 15 and the side of the irradiation ports 16 when the horizontal-direction imaging unit 21 is used.

A method of generating a radiotherapy plan for ion therapy, wherein the beam (6) is shaped by means of passive devices is arranged to allow variation in settings of at least one of the passive devices and/or the MU during the delivery of the beam and to control the movement of the patient and/or the beam in such a way as to create an arc. The arc is preferably a continuous arc or includes at least one continuous sub-arc. The method may include forward planning or optimization. In the latter case, the optimization uses an optimization problem set up to allow variation in settings of at least one of the range modulating device (9), the aperture element (11) and the MU during the delivery of the arc. Computer programs control the planning and the delivery.

A neutron capture therapy system is provided, including a neutron generating device and a beam shaping assembly. The neutron capture therapy system further includes a concrete wall forming a space for accommodating the neutron generating device and the beam shaping assembly and shielding radiations generated by the neutron generating device and the beam shaping assembly. A support module is disposed in the concrete wall, the support module is capable of supporting the beam shaping assembly and is used to adjust the position of the beam shaping assembly, and the support module includes concrete and a reinforcing portion at least partially disposed in the concrete. The neutron capture therapy system designs a locally adjustable support for the beam shaping assembly, so that the beam shaping assembly can meet the precision requirement, improve the beam quality, and meet an assembly tolerance of the target.