An X-ray source, which includes a resonant cavity preferably of a cylindrical shape, is excited in a microwave mode TE.sub.11p and affected by a static and non-homogeneous magnetic field that grows longitudinally. An electron beam is injected longitudinally through one of the lateral walls of the cavity and is continuously accelerated until it reaches an energy sufficient to produce X-rays after the electrons bombard a metallic target located in the plane where they stop their longitudinal movement. The profile of the magnetic field grows in such a way that it maintains the conditions of electron cyclotron resonance along the helical paths of the electrons, The device can be used to obtain radiographic images and even produce hard X-rays.

A cyclotron includes a pole; a superconductive coil wound so as to cover an outer periphery of the pole; a coil support that supports the superconductive coil; a cooling part that cools the superconductive coil; a first support that is connected to the coil support and is capable of adjusting a position of the coil support in a direction of a winding central axis of the superconductive coil; and a second support that is connected to the coil support and is capable of adjusting the position of the coil support in an orthogonal direction orthogonal to the direction of the winding central axis of the superconductive coil. The second support has a link mechanism that is displaceable in each of the direction of the winding central axis and the orthogonal direction.

The invention specifies the use of feedback in the radio frequency (RF) drive for a synchrocyclotron, controlling the phase and/or amplitude of the accelerating field as a means to assure optimal acceleration of the beam, to increase the average beam current and to alter the beam orbit in order to allow appropriate extraction as the beam energy is varied. The effect of space charge is reduced by rapid acceleration and extraction of the beam, and the repetition rate of the pulses can be increased. Several means are presented to monitor the phase of the beam in synchrocyclotrons and to adjust the phase and amplitude of the RF to optimize the acceleration of the beam and to adjust the extraction and injection of the beam. Also, the use of a pulsed ion source that matches the acceptance window of the synchrocyclotron is described.

The invention specifies the use of feedback in the radio frequency (RF) drive for a synchrocyclotron, controlling the phase and/or amplitude of the accelerating field as a means to assure optimal acceleration of the beam, to increase the average beam current and to alter the beam orbit in order to allow appropriate extraction as the beam energy is varied. The effect of space charge is reduced by rapid acceleration and extraction of the beam, and the repetition rate of the pulses can be increased. Several means are presented to monitor the phase of the beam in synchrocyclotrons and to adjust the phase and amplitude of the RF to optimize the acceleration of the beam and to adjust the extraction and injection of the beam. Also, the use of a pulsed ion source that matches the acceptance window of the synchrocyclotron is described.

The invention, which relates to a miniaturizable plasma thruster, consists of: igniting the plasma by microhollow cathode discharge close to the outlet and inside the means for injecting the propellant gas, said injection means being magnetic and comprising a tip at the downstream end thereof; bringing the electrons of the magnetized plasma into gyromagnetic rotation, at the outlet end of said injection means; sustaining the plasma by means of Electron Cyclotron Resonance (ECR), said injection means being metal and being used as an antenna for electromagnetic (EM) emission, the volume of ECR plasma at the outlet of said injection means being used as a resonant cavity of the EM wave; accelerating the plasma in a magnetic nozzle by diamagnetic force, the ejected plasma being electrically neutral.

A disturbance magnetic field region provided in an outer peripheral portion of a main magnetic field region of an accelerator has a peeler region in which a strength of a magnetic field decreases toward an outside, a regenerator region in which the strength of the magnetic field increases toward the outside, and a substantially flat region in which the strength of the magnetic field is larger than the strength of the magnetic field of the peeler region and smaller than the strength of the magnetic field of the regenerator region.

A magnetic orbital angular momentum beam accelerator will accelerate charged particles, electrons or ions, from rest in zero or low magnetic field into a high magnetic field regions with high kinetic energies in the form of magnetic orbital angular momentum. For example, a beam injector that accelerates electrons or ions into 1T magnetic fields with tens of keV kinetic energies transverse to the magnetic fields can be used to heat magnetically confined plasmas, to inject an initial energetic plasma component with high magnetic orbital angular momentum and to produce highly transverse particle momenta to the magnetic field for electron or ion beam lithography.

Various emitters and emitter systems are disclosed. For instance, in various embodiments, an emitter can comprise a substrate, an insulator bonded to the substrate, a graphene layer bonded to the insulator, and a first electrical contact and a second electrical contact. The first electrical contact can be bonded over a first portion of the graphene layer, and the second electrical contact can be bonded over a second portion of the graphene layer. The graphene layer electrically couples the first electrical contact and the second electrical contact and is configured to receive the application of a pulsed input voltage between the first electrical contact and the second electrical contact and to radiate radio frequency (RF) energy. An emitter system can comprise a plurality of emitters, each disposed on a single integrated circuit.

An acceleration voltage measurement circuit outputs an acceleration voltage signal V.sub.acc as a measurement signal in which an acceleration radiofrequency voltage excited in the accelerating cavity is measured. A low power radiofrequency control system inputs, to the accelerating cavity, as radiofrequency power, control radiofrequency power at a constant frequency included in the range of the resonance frequency of the accelerating cavity. When the phase difference between the acceleration voltage signal V.sub.acc and the control radiofrequency power becomes within the predetermined value, the low power radiofrequency control system inputs, to the accelerating cavity, as radiofrequency power by feedback control, the acceleration radiofrequency power synchronized with the acceleration frequency that is the frequency of the acceleration voltage signal V.sub.acc, and thereafter, when the acceleration frequency reaches an output frequency F.sub.ext, stops the input of the acceleration radiofrequency power to the accelerating cavity.

In one embodiment of the invention, a method for irradiating a target is disclosed. A proton beam is generated using a cyclotron. A first information is provided to an energy selection system. An energy level for the protons is selected using an energy selection system based on the first information. The first information comprises a depth of said target. The proton beam is routed from the cyclotron through a beam transfer line to a scanning system. A second information is provided to the scanning system. The second information comprises a pair of transversal coordinates. The proton beam is guided to a location on the target determined by the second information using a magnet structure. The target is irradiated with the protons.