An example particle therapy system includes: a synchrocyclotron to output a particle beam; a magnet to affect a direction of the particle beam to scan the particle beam across at least part of an irradiation target; scattering material that is configurable to change a spot size of the particle beam, where the scattering material is down-beam of the magnet relative to the synchrocyclotron; and a degrader to change an energy of the beam prior to output of the particle beam to the irradiation target, where the degrader is down-beam of the scattering material relative to the synchrocyclotron.

An example method includes: receiving, from a treatment planning process, information that is based on a dose distribution for an irradiation target; and performing at least one of the following operations: moving structures to trim spots of a particle beam so that the spots of the particle beam approximate pre-trimmed spots for which characteristics are obtained based on the information received; moving structures to produce a trimming curve for a layer of an irradiation target based on a specification of a trimming curve for the layer included in the information received; moving structures to produce a single trimming curve for all radiation fields of an irradiation target based on specifications of the single trimming curve included in the information received; or moving structures based on configuration information for the structures in the information received.

An example method includes: receiving, from a treatment planning process, information that is based on a dose distribution for an irradiation target; and performing at least one of the following operations: moving structures to trim spots of a particle beam so that the spots of the particle beam approximate pre-trimmed spots for which characteristics are obtained based on the information received; moving structures to produce a trimming curve for a layer of an irradiation target based on a specification of a trimming curve for the layer included in the information received; moving structures to produce a single trimming curve for all radiation fields of an irradiation target based on specifications of the single trimming curve included in the information received; or moving structures based on configuration information for the structures in the information received.

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.

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.

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.

An example system includes: a magnet including one or more coils to conduct current to generate a magnetic field, with the magnetic field to affect output of radiation to a target; and one or more actuators, with an actuator among the one or more actuators being at least part of a physical coupling to the one or more coils, and with the actuator being controllable to move the one or more coils via the physical coupling based on movement of the magnet.

An example particle accelerator includes a coil to provide a magnetic field to a cavity; a particle source to provide a plasma column to the cavity; a voltage source to provide a radio frequency (RF) voltage to the cavity to accelerate particles from the plasma column, where the magnetic field causes particles accelerated from the plasma column to move orbitally within the cavity; an enclosure containing an extraction channel to receive the particles accelerated from the plasma column and to output the received particles from the cavity; and a structure arranged proximate to the extraction channel to change an energy level of the received particles.

An example particle accelerator includes a coil to provide a magnetic field to a cavity; a particle source to provide a plasma column to the cavity; a voltage source to provide a radio frequency (RF) voltage to the cavity to accelerate particles from the plasma column, where the magnetic field causes particles accelerated from the plasma column to move orbitally within the cavity; an enclosure containing an extraction channel to receive the particles accelerated from the plasma column and to output the received particles from the cavity; and a structure arranged proximate to the extraction channel to change an energy level of the received particles.

An example particle therapy system may include: a synchrocyclotron to produce a particle beam; a scanner to move the particle beam in one or more dimensions relative to an irradiation target; and an energy degrader that is between the scanner and the irradiation target. The energy degrader may include multiple plates that are movable relative to a path of the particle beam, with the multiple plates each being controllable to move while in the path of the particle beam and during movement of the particle beam. An aperture may be between the energy degrader and the irradiation target. The aperture being may be to trim the particle beam prior to the particle beam reaching the irradiation target.