An apparatus may include a drift tube assembly, comprising a plurality of drift tubes to conduct an ion beam along a beam propagation direction. The plurality of drift tubes may define a multi-gap configuration corresponding to a plurality of acceleration gaps, wherein the plurality of drift tubes further define a plurality of RF quadrupoles, respectively. As such, the plurality of quadrupoles are arranged to defocus the ion beam along a first direction at the plurality of acceleration gaps, respectively, where the first direction extends perpendicularly to the beam propagation direction.

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 that generates short charged particle packets or pulses (e.g., electron packets) without requiring a fast-switching-laser source is described. This system may include a charged particle source that produces a stream of continuous charged particles to propagate along a charged particle path. The system also includes a charged particle deflector positioned in the charged particle path to deflect the stream of continuous charged particles to a set of directions different from the charged particle path. The system additionally includes a series of beam blockers located downstream from the charged particle deflector and spaced from one another in a linear configuration as a beam-blocker grating. This beam-blocker grating can interact with the deflected stream of charged particles and divide the stream of the charged particles into a set of short particle packets. In one embodiment, the charged particles are electrons. The beam blockers can be conductors.

A new ring coupling structure for a linear accelerator includes an acceleration cavity, a coupling cavity, and a beam hole. The acceleration cavity and the coupling cavity are alternately assembled together. The beam hole penetrates through the acceleration cavity and the coupling cavity. The acceleration cavity adopts a bowl-shaped structure, a convex cone structure with a mesoporous is disposed on an inner wall of the acceleration cavity along the beam hole. Coupling holes between the acceleration cavity and the coupling cavity are designed as at least two waist-shaped holes uniformly distributed around the beam hole. The coupling cavity adopts a disc-shaped cavity structure with a thickened edge, and a nose cone is disposed in the coupling cavity and welded with cavity walls at both ends of a coupler. The left and right waveguide plates of the coupling cavity are welded together by using the nose cone.

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.

Electron beam collimators and linear accelerators include a target and a collimator body. The collimator body has a central aperture that opens at an exit to the target and has a final internal diameter at the exit that defines an electron beam spot size on the target.

An ion implantation apparatus includes: a multistage linear acceleration unit including a plurality of stages of high-frequency resonators and a plurality of stages of focusing lenses; a first beam measuring unit disposed in the middle of the multistage linear acceleration unit and configured to allow passage of a beam portion adjacent to a center of a beam trajectory and measure a current intensity of another beam portion blocked by an electrode body outside a vicinity of the center of the beam trajectory; a second beam measuring unit disposed downstream of the multistage linear acceleration unit and configured to measure a current intensity of an ion beam exiting from the multistage linear acceleration unit; and a control device configured to adjust a control parameter of the plurality of stages of focusing lenses based on measurement results of the first and second beam measuring units.

An electron acceleration system includes a first RF cavity, and a second RF cavity whose center is located at a distance not more than 1.5 inch from the center of the first RF cavity, along an axis. The first RF cavity has a length less than about 0.25 inches. The on-axis coupling between the first and second RF cavities along the axis, which is primarily electric, is cancelled out by an off-axis coupling between the RF cavities off the axis, which is primarily magnetic. In this way, the net RF coupling between the RF cavities is zero. The phase and amplitude of the first and second RF cavities are each independently adjustable.

An electron acceleration system includes a first RF cavity, and a second RF cavity whose center is located at a distance not more than 1.5 inch from the center of the first RF cavity, along an axis. The first RF cavity has a length less than about 0.25 inches. The on-axis coupling between the first and second RF cavities along the axis, which is primarily electric, is cancelled out by an off-axis coupling between the RF cavities off the axis, which is primarily magnetic. In this way, the net RF coupling between the RF cavities is zero. The phase and amplitude of the first and second RF cavities are each independently adjustable.