Abstract: A magnetron includes an anode cylinder which has a cylindrical shape with both ends opened and which includes a plurality of vanes radially provided on an inner wall surface thereof, a pair of pole pieces positioned in openings of the both ends of the anode cylinder, and metal sleeves. The metal sleeves are positioned outside the pair of pole pieces and configured to air-tightly seal the anode cylinder. Each of the metal sleeves includes a cylinder part, a flange part continuous with the cylinder part, and a plurality of protrusions provided on a portion in which the cylinder part continues with the flange part.

Abstract: An ion therapy system comprises a particle accelerator (1) mounted on a rotatable gantry (2). The particle accelerator includes a superconducting coil (17) which rotates about its axis as the particle accelerator rotates about the gantry axis in use to direct an output beam towards a target from different directions. The particle accelerator is rotatable through (180) degrees to move the beam through a corresponding arc. The particle accelerator includes cooling system arranged to cool the coil as the coil rotates. The superconducting coil (17) is mounted in a coil support (25). The coil is surrounded by a cryogen chamber (32) which is located radially outwardly from the coil (17) on the other side of the support (25). The cryogen chamber is in fluid communication with a cryogen recondensing unit (29) whereby vaporized cryogen may flow from the cryogen chamber (32) to the cryogen recondensing unit (29) to be recondensed in use before returning to the cryogen chamber.

Abstract: An electrode tile configuration is disclosed. The tile has contoured edges dimensioned to control any coupling effects. A plurality of tiles in a matrix configuration is also described.

Abstract: A method is described wherein a beam of charged particles is confined to an orbit within a compact region of space as it is accelerated across a wide range of energies. This confinement is achieved using a non-scaling magnetic field based on the Fixed Alternating Gradient principle where the field strength includes non-linear components. Examples of magnet configurations designed using this method are disclosed.

Abstract: An electron tube includes: a microwave structure having an evacuated envelope including two ends, the microwave structure being at a reference potential, an electron gun including a cathode for providing a beam of electrons, along an axis, at one end of the evacuated envelope, an electron collector for gathering electrons of the beam at the other end of the evacuated envelope, and at least one high-voltage power supply for applying to the cathode a negative high-voltage potential with respect to the reference potential. The tube includes between the cathode and the microwave structure a device for extracting the positive ions including at least one electrode carried to a negative potential with respect to the reference potential so as to extract positive ions from the evacuated envelope, these positive ions being produced by the impacting of the electrons of the electron beam with molecules of residual gas in the evacuated envelope. The invention has application to microwave electron tubes, klystron TWT etc.

Abstract: A driving circuitry arranged to pass a dead time over an isolation transformer, the driving circuitry constituted of: a three-state driver arranged to output a first signal, the first signal selectively at one of two complementary voltage levels and a high impedance state; a first capacitor, a first end of the first capacitor coupled to receive the first signal; and a first isolation transformer, a first end of a first winding of the first isolation transformer coupled to a second end of the first capacitor.

Abstract: A method for generating stabilized particle acceleration by a radio-frequency (RF) accelerator is described, comprising operating the accelerator in a warm-up mode during a warm-up time period, without injecting charged particles or without accelerating injected charged particles, and operating the accelerator in a beam-on mode during a beam-on time period after the warm-up time period, to accelerate charged particles injected by the charged particle source. Automatic frequency control to match an expected frequency of the accelerator during the beam-on time period, prior to the start of the beam-on time period, for stability, is also described.

Abstract: An electron cyclotron resonance ion generator includes a vacuum-tight chamber configured to contain a plasma, a magnetic field generator configured to generate a magnetic field in the chamber, a waveguide configured to propagate a high-frequency wave inside the chamber, a first ionization stage located at one end of the chamber, the first stage including an ionization zone in which ions are generated, the magnetic field being approximately parallel to a longitudinal axis in the ionization zone, a second magnetic confinement stage for the ions generated in the ionization zone, the second stage using a first high-frequency wave being propagated in the chamber from the waveguide, the magnetic field being approximately parallel to the longitudinal axis between the ionization zone and the second confinement stage, such that the ions generated in the ionization zone migrate towards the second confinement stage and the first and second stages contain the same continuous plasma.

Abstract: A charged particle beam generator, a charged particle irradiation system, a method for operating the charged particle beam generator and a method for operating the charged particle irradiation system, which allow a charged particle beam to be injected into a circular accelerator at an arbitrary timing and can reduce an irradiation time and a time for a therapy, are provided while maintaining the lower limit of an operation cycle of a linear accelerator. An accelerator control device controls an operation of a synchrotron on the basis of a beam extraction request signal transmitted from a beam utilization system control device. A control device generates a timing signal notifying the linear accelerator of an injection timing of a next operation cycle of the synchrotron after completion of an extraction process performed by the synchrotron, changes an operation timing of the linear accelerator so that the operation timing of the linear accelerator matches the injection timing.

Abstract: A circular accelerator comprises a target current value memory which stores a target current value of a beam current of charged particle which is extracted from an extracting device; and a frequency determination part in which a frequency change ratio is obtained by performing a feedback control based on an error signal between a detection signal of a beam current detector and a target current value which is stored in a target current value memory, and determines a subsequent frequency from the obtained frequency change ratio and a current frequency, wherein the subsequent frequency which is determined by the frequency determination part is stored in a frequency memory and a radio-frequency generator generates the subsequent radio-frequency of frequency which is determined.

Abstract: An apparatus for generating an electron beam is disclosed to reduce emittance of an electron beam. The apparatus includes: a housing including a rear portion where an electron beam is generated, a front portion having an electron beam discharge hole for discharging the electron beam to the exterior, and a side portion connecting the rear portion and the front portion, the side portion having a first hole and an opposite side portion, facing the first hole, having a second hole in order to reduce asymmetry of an electric field caused by the first hole; and a waveguide installed on the side portion to supply an electromagnetic wave to the interior of the housing through the first hole, wherein the electron beam is generated by laser incident to the interior of the housing and accelerated by the electromagnetic wave supplied to the interior of the housing.

Abstract: The temperature rise due to the backstreaming electrons is canceled by an equal and opposite fall in temperature at the surface of the cathode due to the conduction of heat deposited at the surface immediately prior to the microwave pulse by a pulsed laser focused to uniformly illuminate the cathode surface. Variations in temperature across the surface of the cathode attributable to the non-uniform spatial distribution of the backstreaming electrons may be compensated using a second laser pulse fired during the RF pulse to maintain constant thermal power input across the surface of the cathode during the RF pulse. This second pulse can also be used to compensate for the time-dependent rate of decay of temperature due to conduction of the heat deposited by the first laser into the body of the cathode.

Abstract: A magnetron includes an anode cylinder; a cathode side tube hermetically coupled to a lower portion of the anode cylinder; and a shield cylinder. The shield cylinder includes a cylindrical part extending in substantially a vertical direction, a flange part which is connected to the cylindrical part and extends in substantially a horizontal direction over the entire periphery of the cylindrical part, and a folded part in which a portion of the flange part is folded toward the cathode side tube. The shield cylinder is electrically coupled to the cathode side tube at a lower end of the anode cylinder.

Abstract: A d. c. charged particle accelerator comprises accelerator electrodes separated by insulating spacers defining acceleration gaps between adjacent pairs of electrodes. Individually regulated gap voltages are applied across each adjacent pair of accelerator electrodes. In an embodiment, direct connections are provided to gap electrodes from the stage points of a multistage Cockcroft Walton type voltage multiplier circuit. The described embodiment enables an ion beam to be accelerated to high energies and high beam currents, with good accelerator stability.

Abstract: Systems and methods may be provided for cylindrical Hall thrusters with independently controllable ionization and acceleration stages. The systems and methods may include a cylindrical channel having a center axial direction, a gas inlet for directing ionizable gas to an ionization section of the cylindrical channel, an ionization device that ionizes at least a portion of the ionizable gas within the ionization section to generate ionized gas, and an acceleration device distinct from the ionization device. The acceleration device may provide an axial electric field for an acceleration section of the cylindrical channel to accelerate the ionized gas through the acceleration section, where the axial electric field has an axial direction in relation to the center axial direction. The ionization section and the acceleration section of the cylindrical channel may be substantially non-overlapping.

Abstract: Methods and apparatus are disclosed for providing combined time-varying light comprising light from one or more light sources (132, 134, 136), and determining aspects of light from one or more light sources based on measurements of the combined light. Light sources of one or more colors can be controlled to provide time-varying combined light outputs (310, 360) using different switching sequences for different light sources, for example according to PWM, PCM, or other modulation methods. By appropriately configuring the timing of the switching sequences, the combined light output can be made to exhibit a plurality of lighting combinations. A broadband optical sensor (148) can be configured to measure (145) some or all of the plurality of lighting combinations, and the measurements used to determine light output measurements of portions of the combined light, and optionally of ambient light, by appropriate processing (150) of the measurements.

Abstract: A particle accelerator including an electrical field system and a magnetic field system that are configured to direct charged particles along a desired path within an acceleration chamber. The particle accelerator also includes a mechanical device that is located within the acceleration chamber. The mechanical device is configured to be selectively moved to different positions within the acceleration chamber. The particle accelerator also includes an electromechanical (EM) motor having a connector component and piezoelectric elements that are operatively coupled to the connector component. The connector component is operatively attached to the mechanical device. The EM motor drives the connector component when the piezoelectric elements are activated thereby moving the mechanical device.

Abstract: An accelerator pack, specifically for linear accelerator modules cascade-connected to a proton-emitting cyclotron, specially adapted for use in cancer therapies. Such a technique is named PT. The pack displays an accelerating cavity of improved efficiency in virtue of its shape, which provides for making a portion of accelerating cavity on both faces of the pack. Furthermore, the pack also contains a coupling cavity portion. In such a manner, the volume of the accelerating cavity is increased as compared to that of the packs of the known accelerator modules.

Abstract: An electron injector including an electron source and a conducting grid situated close to the electron source, one or more RF accelerating/bunching cavities operating at the same fundamental RF frequency; a DC voltage source configured to bias the cathode at a small positive voltage with respect to the grid; a first RF drive configured to apply an RF signal between the cathode and grid at the fundamental and third harmonic RF frequencies; and a second RF drive configured to apply an RF drive signal to the accelerating/bunching cavities. Electrons are emitted by the cathode and travel through the grid to the accelerating/bunching cavities for input into an RF linac.

Abstract: A d.c. charged particle accelerator comprises accelerator electrodes separated by insulating spacers defining acceleration gaps between adjacent pairs of electrodes. Individually regulated gap voltages are applied across each adjacent pair of accelerator electrodes. In embodiments, the individually regulated gap voltages are generated by electrically isolated alternators mounted on a common rotor shaft driven by an electric motor. Alternating power outputs from the alternators provide inputs to individual regulated d.c. power supplies to generate the gap voltages. The power supplies are electrically isolated and have outputs connected in series across successive pairs of accelerator electrodes. The described embodiment enables an ion beam to be accelerated to high energies and high beam currents, with good accelerator stability.