Abstract: Some embodiments include an accelerator waveguide having a plurality of cavities, and at least two RF power sources, each of the at least two RF power sources being separately coupled to a respective one of the plurality of cavities.

Abstract: Some embodiments include operation of an accelerator waveguide to output first particles from a tuned end cavity of the accelerator waveguide at a first energy, detuning of the end cavity, and operation of the accelerator waveguide to output second particles from the detuned end cavity at a second energy.

Abstract: Some embodiments include an accelerator waveguide having a plurality of cavities, and at least two RF power sources, each of the at least two RF power sources being separately coupled to a respective one of the plurality of cavities.

Abstract: Some embodiments include operation of an accelerator waveguide to output first particles from a tuned end cavity of the accelerator waveguide at a first energy, detuning of the end cavity, and operation of the accelerator waveguide to output second particles from the detuned end cavity at a second energy.

Abstract: Some embodiments include operation of an accelerator waveguide to accelerate particles to a first energy within the waveguide, wherein a prebuncher coupled to the waveguide outputs particle bunches having a first phase, change of a phase at which particle bunches will be output from the prebuncher from the first phase to a second phase, and operation of the accelerator waveguide to accelerate particles to a second energy within the waveguide, wherein the prebuncher outputs particle bunches having the second phase. Further aspects provide change of a resonant frequency of the prebuncher from a first frequency to a second frequency. According to still further aspects, the prebuncher includes a prebuncher cavity and change of the resonant frequency comprises change of a shape of the prebuncher cavity.

Abstract: Some embodiments include operation of an accelerator waveguide to accelerate particles to a first energy within the waveguide, wherein a prebuncher coupled to the waveguide outputs particle bunches having a first phase, change of a phase at which particle bunches will be output from the prebuncher from the first phase to a second phase, and operation of the accelerator waveguide to accelerate particles to a second energy within the waveguide, wherein the prebuncher outputs particle bunches having the second phase. Further aspects provide change of a resonant frequency of the prebuncher from a first frequency to a second frequency. According to still further aspects, the prebuncher includes a prebuncher cavity and change of the resonant frequency comprises change of a shape of the prebuncher cavity.

Abstract: A method, system, and apparatus for providing reduced dark current in a linear accelerator includes a cavity having an input aperture and an output aperture, and a particle source coupled to the input aperture, the input aperture having a radius greater than a radius of the output aperture.

Abstract: An improved method, system, and apparatus for tuning a particle accelerator is provided which includes tuning side cavities while placing adjancent cavities in a de-tuned condition. A conductor is positioned such that a primary cavity under test is minimally excited, while adjacent side cavities are excited. Coupled modes are measured. The primary cavity is tuned based on the measured coupled modes. According to the invention, this tuning is accomplished without use of access ports to the interior of the side cavities.

Abstract: A method, system, and apparatus for providing reduced dark current in a linear accelerator includes a cavity having an input aperture and an output aperture, and a particle source coupled to the input aperture, the input aperture having a radius greater than a radius of the output aperture.

Abstract: The invention provides a scheme in accordance with which a linear accelerator may be operated in two or more resonance (or standing wave) modes to produce charged particle beams over a wide range of output energies so that diagnostic imaging and therapeutic treatment may be performed on a patient using the same device. In this way, the patient may be diagnosed and treated, and the results of the treatment may be verified and documented, without moving the patient. This feature reduces alignment problems that otherwise might arise from movement of the patient between diagnostic and therapeutic exposure machines. In addition, this feature reduces the overall treatment time, thereby reducing patient discomfort.

Abstract: A radio frequency (RF) modulated electron gun includes a cathode, electrically coupled to operate as a source of charged particles, and a grid, positioned apart from the cathode. The grid and the cathode are electrically coupled to a grid voltage source and to a RF source. The grid voltage source places the grid at a first potential, and the RF source places the grid at a second potential selected to produce groups of the charged particles. The groups of charged particles are produced with each period of a signal received from the RF source.

Abstract: A standing wave linear accelerator with a prebunching section and an accelerating section that are formed into a unitary accelerating structure is described. The prebunching section is configured to group charged particles into bunches by velocity modulation of the charged particle beam. The accelerating section has a plurality of inter-coupled resonant cavities, including an input cavity that is coupled to the prebunching section and an output cavity.

Abstract: The invention provides a scheme in accordance with which a linear accelerator may be operated in two or more resonance (or standing wave) modes to produce charged particle beams over a wide range of output energies so that diagnostic imaging and therapeutic treatment may be performed on a patient using the same device. In this way, the patient may be diagnosed and treated, and the results of the treatment may be verified and documented, without moving the patient. This feature reduces alignment problems that otherwise might arise from movement of the patient between diagnostic and therapeutic exposure machines. In addition, this feature reduces the overall treatment time, thereby reducing patient discomfort.

Abstract: A radiation therapy system according to the present invention includes a treatment system and an imaging system. The treatment system employs a first tungsten target to generate high power X-rays for treatment. The imaging system uses a second target to generate low power X-rays for imaging. The targets are arranged such that the resulting treatment and imaging beams are generally collinear.

Abstract: Systems and methods for reducing dark current levels in a standing wave linear accelerator without sacrificing operating performance are described. In a radiation mode, the standing wave linear accelerator is operated to produce a pulsed therapeutic photon beam having a characteristic pulse width. In an electron mode, the standing wave linear accelerator is operated to produce a pulsed therapeutic electron beam having a characteristic pulse width that is shorter than the characteristic pulse width of the therapeutic photon beam. In some embodiments, assuming a uniform dark current level, the dark current level may be reduced in proportion with the beam pulse width reduction in the electron mode of operation. A system for implementing this therapeutic beam generation method also is described.

Abstract: An article irradiation system includes a radiation source for scanning a target region with radiation; a first conveyor system for transporting articles from a loading area though the target region to an unloading area; and radiation shielding material defining a tunnel closely encompassing portions of the conveyor system extending away from the target region toward the loading and unloading areas for shielding the loading and unloading areas from radiation derived from the radiation source. The first conveyor system is disposed in a path having curved turns of such degree between the target region and the loading and unloading areas that the closely encompassing radiation shielding material precludes a direct line of sight between the target region and the loading and unloading areas and thereby facilitates a compact embodiment in which the first conveyor system may be included in an assembly line.

Abstract: A linear accelerator includes cascaded standing wave main cavities with approximately the same resonant frequency and plural side cavities. A charged particle beam travels longitudinally through the main cavities. An electromagnetic wave excites the cavities with a frequency that is approximately the same as the resonant frequency of the main cavities. There is normally a fixed electromagnetic energy phase shift in adjacent main cavities. The resonant frequency of at least one side cavity is adjusted so it differs from the electromagnetic wave frequency. The detuned side cavity resonant frequency causes: (a) a change in the normal fixed phase shift of the main cavities adjacent the one side cavity and (b) a decrease in electric field strength in cavities electromagnetically downstream of the one side cavity relative to the electric field strength in cavities electromagnetically upstream of the one side cavity.