The invention relates to a drum assembly for a linear accelerator, the drum assembly comprising a drum having a front face including a front rim and a rear face including a rear rim, one or more support wheels supporting the drum, an arm extending from the front face of the drum and including a beam collimator through which a beam of radiation is emitted to form a radiation isocentre. One or more rear rim members are associated with the rear rim, the rear rim members adapted to substantially offset isocentre distortion due to unintended movement of the drum assembly. The invention also relates to variants thereto and combinations thereof.

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 dose.

Methods and system for facilitating rapid radiation treatments are provided herein and relate in particular to radiation generation and delivery, electron source design, beam control and shaping/intensity-modulation. The methods and systems described herein are particularly advantageous when used with a compact high-gradient, very high energy electron (VHEE) accelerator and delivery system (and related processes) capable of treating patients from multiple beam directions with great speed, using all-electromagnetic or radiofrequency deflection steering is provided; or when used with a high-current electron accelerator system of energy range more conventionally used in photon radiation therapy to produce much faster delivery of intensity-modulated photon radiation therapy, that can in both cases deliver an entire dose or fraction of high-dose radiation therapy sufficiently fast to freeze physiologic motion, yet with an equal or better degree of dose conformity or sculpting compared to conventional photon therapy.

A compact radio-frequency quadrupole RFQ accelerator for accelerating charged particles, the RFQ accelerator comprising: a bunching section configured to have a narrow radio-frequency rf acceptance such that only a portion of a particle beam incident on the bunching section is captured, and wherein the bunching section bunches the portion of the particle beam; an accelerating section for accelerating the bunched portion of the particle beam to an output energy; and, a means for supplying radio-frequency power.

When accelerating first ions, radio frequency power is fed to a drift tube linear accelerator so that the phase difference between an accelerating half cycle for accelerating the first ions in one of the plurality of drift tube gaps and the accelerating half cycle for accelerating the accelerated first ions reaching the next drift tube gap is set to a first accelerating cycle phase difference; and when accelerating second ions having a charge-to-mass ratio lower than the first ions, the radio frequency power is fed to the drift tube linear accelerator so that the phase difference between an accelerating half cycle for accelerating the second ions in the one drift tube gap and the accelerating half cycle for the accelerated second ions reaching the next drift tube gap is set to a second accelerating cycle phase difference that is larger than the first accelerating cycle phase difference.

A linear accelerator head for use in a medical radiation therapy system can include a housing, an electron generator configured to emit electrons along a beam path, and a microwave generation assembly. The linear accelerator head may include a waveguide that is configured to contain a standing or travelling microwave. The waveguide can include a plurality of cells that are disposed adjacent one another, wherein each of the plurality of cells may define an aperture configured to receive electrons therethrough. The linear accelerator head can further include a converter and a primary collimator.

A linear accelerator head for use in a medical radiation therapy system can include a housing, an electron generator configured to emit electrons along a beam path, and a microwave generation assembly. The linear accelerator head may include a waveguide that is configured to contain a standing or travelling microwave. The waveguide can include a plurality of cells that are disposed adjacent one another, wherein each of the plurality of cells may define an aperture configured to receive electrons therethrough. The linear accelerator head can further include a converter and a primary collimator.

A system has a linear accelerator, ion pump and a compensating magnet. The ion pump includes an ion pump magnet position, an ion pump magnet shape, an ion pump magnet orientation, and an ion pump magnet magnetic field profile. The compensating magnet has a position, a shape, an orientation, and a magnetic field profile, where at least one of the position, shape, orientation, and magnetic field profile of the compensating magnet reduce at least one component of a magnetic field in the linear accelerator resulting from the ion pump magnet.

A hybrid linear accelerator is disclosed comprising a standing wave linear accelerator section (SW section) followed by a travelling wave linear accelerator section (TW section). In one example, RF power is provided to the TW section and power not used by the TW section is provided to the SW section via a waveguide. An RF switch, an RF phase adjuster, and/or an RF power adjuster is provided along the waveguide to change the energy and/or phase of the RF power provided to the SW section. In another example, RF power is provided to both the SW section and the TW section, and RF power not used by the TW section is provided to the SW section, via an RF switch, an RF phase adjuster, and/or an RF power. In another example, an RF load is matched to the output of the TW section by an RF switch.

A hybrid linear accelerator is disclosed comprising a standing wave linear accelerator section (SW section) followed by a travelling wave linear accelerator section (TW section). In one example, RF power is provided to the TW section and power not used by the TW section is provided to the SW section via a waveguide. An RF switch, an RF phase adjuster, and/or an RF power adjuster is provided along the waveguide to change the energy and/or phase of the RF power provided to the SW section. In another example, RF power is provided to both the SW section and the TW section, and RF power not used by the TW section is provided to the SW section, via an RF switch, an RF phase adjuster, and/or an RF power. In another example, an RF load is matched to the output of the TW section by an RF switch.