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 doses.

A particle accelerator can include a first waveguide portion and a second waveguide portion. The first waveguide portion can include a first plurality of cell portions and a first iris portion that is disposed between two of the first plurality of cell portions. The first iris portion can include a first portion of an aperture such that the aperture is configured to be disposed about a beam axis. The first waveguide portion can further include a first bonding surface. The second waveguide portion can include a second plurality of cell portions and a second iris portion that is disposed between two of the second plurality of cell portions. The second iris portion can include a second portion of the aperture. The second waveguide portion can include a second bonding surface.

A particle accelerator can include a first waveguide portion and a second waveguide portion. The first waveguide portion can include a first plurality of cell portions and a first iris portion that is disposed between two of the first plurality of cell portions. The first iris portion can include a first portion of an aperture such that the aperture is configured to be disposed about a beam axis. The first waveguide portion can further include a first bonding surface. The second waveguide portion can include a second plurality of cell portions and a second iris portion that is disposed between two of the second plurality of cell portions. The second iris portion can include a second portion of the aperture. The second waveguide portion can include a second bonding surface.

In a helical resonator ion accelerator ions are injected into a hollow dielectric pipe forming a vacuum chamber along which the ions are accelerated. The dielectric pipe is wrapped with a coil and positioned inside a metal pipe. The dielectric pipe, the coil and the metal pipe are arranged coaxially on an axis along which ions are accelerated. A static or magnetic beam optic is used to radially focus the deuterium ions as they transit the accelerator. A pulse generator coupled to the coil is used to generate a voltage wave pulse. The pulse travels down the axis of the accelerator on the helix formed by the coil. An ion source injects deuterium ions along the dielectric pipe axis. A traveling voltage wave is accelerated by tapering the impedance of the accelerator along the accelerator to reduce the impedance per unit length of the accelerator.

An apparatus for generating high frequency electromagnetic radiation includes a whispering gallery mode resonator, coupled to an output waveguide through a coupling aperture. The resonator has a guiding surface, and supports a whispering gallery electromagnetic eigenmode. An electron source is configured to generate a velocity vector-modulated electron beam, where each electron in the velocity vector-modulated electron beam travels substantially perpendicular to the guiding surface, while interacting with the whispering gallery electromagnetic eigenmode in the whispering gallery mode resonator, generating high frequency electromagnetic radiation in the output waveguide.

An apparatus for generating high frequency electromagnetic radiation includes a whispering gallery mode resonator, coupled to an output waveguide through a coupling aperture. The resonator has a guiding surface, and supports a whispering gallery electromagnetic eigenmode. An electron source is configured to generate a velocity vector-modulated electron beam, where each electron in the velocity vector-modulated electron beam travels substantially perpendicular to the guiding surface, while interacting with the whispering gallery electromagnetic eigenmode in the whispering gallery mode resonator, generating high frequency electromagnetic radiation in the output waveguide.

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.

A Hybrid (SW+TW) Linear Acellerator is disclosed having high beam efficiency and broad energy regulation that is useful for security inspection, non-destructive testing, radiotherapy, and electron beam irradiation of objects. The Hybrid Linear Accelerator (LINAC) provides superior energy regulation, and includes a reversed RF power distribution which substantially improves RF power utilization, thereby eliminating need for an output RF load, and ensuring broad electron beam energy regulation operating in a broad range of input RF power, thereby efficiently running at a variety of input electron beam current intensities at high efficiency. The Hybrid LINAC may be equipped with a fast and/or slow phase shifter and/or a power regulator having a phase shifter and a current regulator, while operating much more efficiently than known LINACS. The Hybrid LINAC permits efficient operation without an external magnetic field, thereby avoiding use of a power-consuming solenoid, consequently reducing cost of production, operation, and maintenance.

A Hybrid (SW+TW) Linear Acellerator is disclosed having high beam efficiency and broad energy regulation that is useful for security inspection, non-destructive testing, radiotherapy, and electron beam irradiation of objects. The Hybrid Linear Accelerator (LINAC) provides superior energy regulation, and includes a reversed RF power distribution which substantially improves RF power utilization, thereby eliminating need for an output RF load, and ensuring broad electron beam energy regulation operating in a broad range of input RF power, thereby efficiently running at a variety of input electron beam current intensities at high efficiency. The Hybrid LINAC may be equipped with a fast and/or slow phase shifter and/or a power regulator having a phase shifter and a current regulator, while operating much more efficiently than known LINACS. The Hybrid LINAC permits efficient operation without an external magnetic field, thereby avoiding use of a power-consuming solenoid, consequently reducing cost of production, operation, and maintenance.