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.

Ion beams are efficiently extracted with an accelerator that includes a circular vacuum container including a pair of circular return yokes facing each other. Six magnetic poles are radially disposed from the injection electrode at the periphery thereof in the return yoke. Six recessions are disposed alternately with the respective magnetic poles in the circumferential direction of the return yoke. In the vacuum container, a concentric trajectory region, in which multiple beam turning trajectories centered around the injection electrode are present, is formed, and an eccentric trajectory region, in which multiple beam turning trajectories eccentric from the injection electrode are present, is formed around the region. In the eccentric trajectory region, the beam turning trajectories are dense between the injection electrode and the inlet of the beam extraction path. Gaps between the beam turning trajectories are wide in a direction 180° opposite to the inlet of the beam extraction path.

There is provided a circular accelerator that accelerates a beam of charged particles circulating in a magnetic field such that a closed orbit for each energy of the beam is eccentric. The circular accelerator includes a beam extraction port for extracting beams of different energies from the closed orbit, a first bending magnet and a second bending magnet that bend the beam extracted from the beam extraction port, and a control unit that controls magnetic field strengths of the first bending magnet and the second bending magnet in accordance with the energy of the extracted beam. When the energy of the extracted beam is a designed maximum energy of the circular accelerator, the control unit excites both the first bending magnet and the second bending magnet to bend the beam.

A linac-based X-ray system for cargo scanning and imaging applications uses linac design, RF power control, beam current control, and beam current pulse duration control to provide stable sequences of pulses having different energy levels or different doses.

The accelerator includes a circular vacuum container which contains a circular return yoke. With respect to the central axis of the vacuum container, an incidence electrode is arranged towards the entrance of a beam emission path inside of the return yoke. Inside of the return yoke, electrodes are arranged radially from the incidence electrode in the periphery of the incidence electrode. Recesses are arranged alternately with the electrodes in the circumferential direction of the return yoke. In the vacuum container, an orbit-concentric region is formed in which multiple beam orbits centered on the incidence electrode are present, and, in the periphery of said region, an orbit-eccentric area is formed in which multiple beam orbits eccentric to the incidence electrode are present. In the orbit-eccentric region, the beam orbits between the incidence electrode and the entrance to the beam emission path are denser.

An apparatus includes an accelerator guide and a shielding structure enclosing the accelerator guide. The accelerator guide includes an electron source at a first end, a target at a second end, and a plurality of accelerating cavities coupled in series along a longitudinal axis between the first end and the second end. The accelerator guide has a contour as viewed in the longitudinal axis. The shielding structure has an inner wall surface defining a contour as viewed in the longitudinal axis generally conformal to the contour of the accelerator guide.

A radiation treatment apparatus includes an accelerator that emits a charged particle beam, a time measurement unit that measures an emission time of the charged particle beam of the accelerator, a first control unit that controls the accelerator based on the emission time measured by the time measurement unit, and an emission determination unit that determines whether or not the accelerator is emitting the charged particle beam while the first control unit is controlling the accelerator. The time measurement unit adds a time, for which a result of a determination performed by the emission determination unit is that the accelerator is emitting the charged particle beam, to the emission time and does not add a time, for which the result of the determination performed by the emission determination unit is that the accelerator is not emitting the charged particle beam, to the emission time.

Disclosed herein are systems and methods for rapidly delivering high doses of radiation, also known as, flash dose radiotherapy or flash radiotherapy. One variation of a system for flash radiotherapy has a plurality of therapeutic radiation sources on a support structure (e.g., a gantry or arm) and configured to toward a patient target region, and a controller in communication with all of the therapeutic radiation sources. The controller is configured to activate the plurality of therapeutic radiation sources simultaneously so that the patient target region rapidly receives a high dose of radiation, e.g. the entire prescribed dose of radiation. In some variations, a flash radiotherapy system has a pulsed, high-power source that may be used to generate an X-ray pulse that delivers a dose having a dose rate from about 7.5 Gy/s to about 70 Gy/s. Flash radiotherapy systems may also include one or more imaging systems mounted on the support structure.

Embodiments disclose an energy degrader for attenuating the energy of a charged particle beam, comprising a first energy attenuation member presenting a beam entry face having the shape of a part of a first helical surface, a second energy attenuation member presenting a beam exit face having the shape of a part of a second helical surface, the beam exit face being positioned downstream of said beam entry face with respect to the beam direction, and a drive assembly for rotating the first and/or the second energy attenuation members about respectively a first and/or a second rotation axis while crossed by the particle beam. The first and second helical surfaces are continuous surfaces and have the same handedness, to enable a more compact degrader with a smaller moment of inertia.