A particle therapy system capable of reducing the installation area and also suppressing a variation in the irradiation beam position is provided. A synchrotron generates a charged particle beam, and a beam delivery system irradiates an irradiation target with a charged particle beam extracted from the synchrotron thereby forming a radiation field. A rotating gantry is provided with the beam delivery system and is rotatable around the irradiation target. Dispersion measuring devices, each of which measures the dispersion of the charged particle beam at the position of the irradiation target at a plurality of rotation angles of the rotating gantry, are also provided. The orbit center of the charged particle beam extracted from the synchrotron and the rotation axis of the rotating gantry are located on substantially the same straight line.

An example particle therapy system includes: a particle accelerator to output a beam of charged particles; and a scanning system to scan the beam across at least part of an irradiation target. An example scanning system includes: a scanning magnet to move the beam during scanning; and a control system (i) to control the scanning magnet to produce uninterrupted movement of the beam over at least part of a depth-wise layer of the irradiation target so as to deliver doses of charged particles to the irradiation target; and (ii) to determine, in synchronism with delivery of a dose, information identifying the dose actually delivered at different positions along the depth-wise layer.

A particle beam adjustment device includes: a position monitor that detects a positional deviation of a particle beam transported from a beam transport section; an interlock device to interrupt irradiation of the particle beam when a positional deviation of the particle beam is detected by the position monitor; a pair of screen monitors that measure position and angle of an axis of the particle beam; a correction electromagnet that controls the axis of the particle beam by adjusting a magnetic field on a basis of a signal indicating the particle beam position and angle measured by the screen monitors; and a beam scanning electromagnet that irradiates an irradiation target with the particle beam. One of the screen monitors is installed outside a treatment room, and the other screen monitor and the position monitor are installed inside the treatment room.

A particle beam transport apparatus includes a vacuum duct, at least one magnet controller, and a scanning magnet. The vacuum duct is configured such that a particle beam advances through the vacuum duct. The magnet controller is disposed around a bent portion of the vacuum duct and is configured to control an advancing direction or shape of the particle beam. The scanning magnet is disposed on the downstream side of the magnet controller in the advancing direction and is configured to scan the particle beam by deflecting each bunch of the particle beam. The magnet controller includes a deflection magnet configured to deflect the advancing direction of the particle beam along the bent portion and a quadrupole magnet configured to converge the particle beam. The deflection magnet and the quadrupole magnet constitute a combined-function magnet arranged at the same point in the advancing direction.

The invention discloses a method for adjusting particle orbit alignment by using a first harmonic in a cyclotron, including the following steps: generating a correcting magnetic field through eight coils symmetrically about the middle plane; arranging the positions of the coils and the currents applied, so that they can generate a first harmonic of which the amplitude and phase are arbitrarily adjustable; according to the actual eccentricity of the particle orbit, adjusting the magnitude and direction of the currents applied to the coils, and optimizing the alignment of the particle trajectory. By controlling an external DC power source of the accelerator and combining the real-time feedback of the beam detection of the accelerator, the invention may perform real-time adjustment during the debugging and operation of the accelerator, with high feasibility and operability; compared with traditional methods, the invention may achieve real-time adjustment during the debugging and operation of the accelerator.

The invention discloses a method for adjusting particle orbit alignment by using a first harmonic in a cyclotron, including the following steps: generating a correcting magnetic field through eight coils symmetrically about the middle plane; arranging the positions of the coils and the currents applied, so that they can generate a first harmonic of which the amplitude and phase are arbitrarily adjustable; according to the actual eccentricity of the particle orbit, adjusting the magnitude and direction of the currents applied to the coils, and optimizing the alignment of the particle trajectory. By controlling an external DC power source of the accelerator and combining the real-time feedback of the beam detection of the accelerator, the invention may perform real-time adjustment during the debugging and operation of the accelerator, with high feasibility and operability; compared with traditional methods, the invention may achieve real-time adjustment during the debugging and operation of the accelerator.

A proton treatment system including a proton accelerator structured to generate a proton beam, a beamline pathway configured to direct the proton beam from the proton accelerator to at least one treatment room, a magnet assembly, including superconducting magnets, located in the beamline pathway and configured to transport the proton beam away from the accelerator into the at least one treatment room, an achromat, configured as an achromatic superconducting magnet assembly, that bends the proton beam away from the proton accelerator toward the at least one treatment room, and a collimator provided inside the achromat and configured to select the proton beam with desired energy levels.

An accelerator 4 includes a circular vacuum container including circular return yokes 5A, 5B. An injection electrode 18 is disposed closer to an inlet of a beam extraction path 20 in the return yoke 5B than a central axis C of the vacuum container. Magnetic poles 7A to 7F are radially disposed from the injection electrode 18 at the periphery of the injection electrode 18 in the return yoke 5B. Recessions 29A to 29F are disposed alternately with the magnetic poles 7A to 7F in the circumferential direction of the return yoke 5B. In the vacuum container, a concentric trajectory region, in which multiple beam turning trajectories centered around the injection electrode 18 are present, is formed, and an eccentric trajectory region, in which multiple beam turning trajectories eccentric from the injection electrode 18 are present, is formed around the region.

A dynamic magnetic field feed device feeds a magnetic field at predetermined timing to a predetermined region through which an ion beam having desired energy circulating in an acceleration space passes, and displaces a circular orbit of the ion beam having the desired energy. An extraction channel is arranged on an outer periphery of a magnetic pole. A position O1 where an ion introduction device introduces ions into the acceleration space is a position closer to the extraction channel relative to a center O2 of the magnetic pole. A region to which the dynamic magnetic field feed device feeds a magnetic field is a region closer to an opening of the extraction channel relative to the position O1 where ions are introduced, and the magnetic field to be fed is a magnetic field in a direction where the main magnetic field is strengthened.

A device and method for generating pulses to activate and deactivate a kicker magnet is provided. When the kicker magnet is deactivated the circuit generates and stores a magnetic field in an inductor. When the kicker magnet is activated, the circuit changes configuration so that the magnetic field and current stored in the inductor can provide the necessary current to activate the kicker magnet is a minimal amount of time. The configuration of the circuit changes via the use of switches. The switches can employ Zener diodes arranged so as to provide protection against high voltage events and rogue neutrinos that may bombard the switches when the kicker magnet is used in the context of deflecting a particle beam.