An example particle accelerator includes the following: a voltage source to provide a radio frequency (RF) voltage to a cavity to accelerate particles from a plasma column, where the cavity has a magnetic field causing particles accelerated from the plasma column to move orbitally within the cavity; an extraction channel to receive the particles accelerated from the plasma column and to output the received particles from the cavity; and a regenerator to provide a magnetic field bump within the cavity to thereby change successive orbits of the particles accelerated from the plasma column so that, eventually, particles output to the extraction channel. The magnetic field is at least 6 Tesla and the magnetic field bump is at most 2 Tesla.

The invention specifies the use of feedback in the radio frequency (RF) drive for a synchrocyclotron, controlling the phase and/or amplitude of the accelerating field as a means to assure optimal acceleration of the beam, to increase the average beam current and to alter the beam orbit in order to allow appropriate extraction as the beam energy is varied. The effect of space charge is reduced by rapid acceleration and extraction of the beam, and the repetition rate of the pulses can be increased. Several means are presented to monitor the phase of the beam in synchrocyclotrons and to adjust the phase and amplitude of the RF to optimize the acceleration of the beam and to adjust the extraction and injection of the beam. Also, the use of a pulsed ion source that matches the acceptance window of the synchrocyclotron is described.

The invention specifies the use of feedback in the radio frequency (RF) drive for a synchrocyclotron, controlling the phase and/or amplitude of the accelerating field as a means to assure optimal acceleration of the beam, to increase the average beam current and to alter the beam orbit in order to allow appropriate extraction as the beam energy is varied. The effect of space charge is reduced by rapid acceleration and extraction of the beam, and the repetition rate of the pulses can be increased. Several means are presented to monitor the phase of the beam in synchrocyclotrons and to adjust the phase and amplitude of the RF to optimize the acceleration of the beam and to adjust the extraction and injection of the beam. Also, the use of a pulsed ion source that matches the acceptance window of the synchrocyclotron is described.

The invention specifies the use of feedback in the radio frequency (RF) drive for a synchrocyclotron, controlling the phase and/or amplitude of the accelerating field as a means to assure optimal acceleration of the beam, to increase the average beam current and to alter the beam orbit in order to allow appropriate extraction as the beam energy is varied. The effect of space charge is reduced by rapid acceleration and extraction of the beam, and the repetition rate of the pulses can be increased. Several means are presented to monitor the phase of the beam in synchrocyclotrons and to adjust the phase and amplitude of the RF to optimize the acceleration of the beam and to adjust the extraction and injection of the beam. Also, the use of a pulsed ion source that matches the acceptance window of the synchrocyclotron is described.

The invention specifies the use of feedback in the radio frequency (RF) drive for a synchrocyclotron, controlling the phase and/or amplitude of the accelerating field as a means to assure optimal acceleration of the beam, to increase the average beam current and to alter the beam orbit in order to allow appropriate extraction as the beam energy is varied. The effect of space charge is reduced by rapid acceleration and extraction of the beam, and the repetition rate of the pulses can be increased. Several means are presented to monitor the phase of the beam in synchrocyclotrons and to adjust the phase and amplitude of the RF to optimize the acceleration of the beam and to adjust the extraction and injection of the beam. Also, the use of a pulsed ion source that matches the acceptance window of the synchrocyclotron is described.

An example particle therapy system includes a gantry having a beamline structure configured to direct a particle beam that is monoenergetic from an output of a particle accelerator towards an irradiation target, where the beamline structure includes magnetic bending elements to bend the particle beam along a length of the beamline structure; and an energy degrader downstream of the beamline structure relative to the particle accelerator, where the energy degrader is configured and controllable to change an energy of the particle beam prior to at least part of the particle beam reaching the irradiation target.

An example particle therapy system includes a gantry having a beamline structure configured to direct a particle beam that is monoenergetic from an output of a particle accelerator towards an irradiation target, where the beamline structure includes magnetic bending elements to bend the particle beam along a length of the beamline structure; and an energy degrader downstream of the beamline structure relative to the particle accelerator, where the energy degrader is configured and controllable to change an energy of the particle beam prior to at least part of the particle beam reaching the irradiation target.

A disturbance magnetic field region provided in an outer peripheral portion of a main magnetic field region of an accelerator has a peeler region in which a strength of a magnetic field decreases toward an outside, a regenerator region in which the strength of the magnetic field increases toward the outside, and a substantially flat region in which the strength of the magnetic field is larger than the strength of the magnetic field of the peeler region and smaller than the strength of the magnetic field of the regenerator region.

A system includes a patient support and an outer gantry on which an accelerator is mounted to enable the accelerator to move through a range of positions around a patient on the patient support. The accelerator is configured to produce a proton or ion beam having an energy level sufficient to reach a target in the patient. An inner gantry includes an aperture for directing the proton or ion beam towards the target.

An example particle therapy system includes the following: a gantry that is rotatable relative to a patient position; a particle accelerator mounted to the gantry, where the particle accelerator is for outputting a particle beam essentially directly to the patient position; and a control system to receive a prescription and to generate machine instructions for configuring one or more operational characteristics of the particle therapy system. At least one of the operational characteristics relates to a rotational angle of the gantry relative to the patient position.