Abstract: A compact accelerating structure comprises an accelerating section and a complementary section which may be used as a bunching section and/or a preaccelerating section, this complementary section being constituted by a first cavity and a second cavity joined to one another and electromagnetically coupled with one another in a direct manner, the second cavity, which is adjacent to the accelerating section, having a length L and being electromagnetically coupled to the first cavity and to the accelerating section in such a manner that the electromagnetic accelerating field is zero in this second cavity.

Abstract: A beam of charged particles is guided along a path including a looped section between two rectilinear stretches, each of these stretches being provided with focusing and centering means. A holder insertable into the outgoing stretch, ahead of a collimator, carries a target designed to emit photons upon being struck by incident particles. The target holder is linked with a retracting mechanism which also controls a diaphragm in the looped path section to narrow its aperture when the target is in place. A dose-equalizing filter utilized in the latter instance is movable jointly with the target holder out of the path of the exiting beam.

Abstract: A high-frequency focusing device making it possible to achieve suitable horizontal and vertical focusing of a beam of charged particles issued from a particle source located substantially at the center of a cyclotron, this device comprising pairs of focusing electrodes fixed to the edges of parallel plates forming each sector-shaped Dees of the cyclotron, each pair of electrodes being arranged in such a manner that the particle beam passes between them, these electrodes which project into the acceleration space e of the cyclotron, making it possible to compensate for lack or excessive vertical focusing brought about by the magnetic field developed in the acceleration space e.

Abstract: A microwave reflector device of small size, making it possible to deliver a predetermined quantity of the power generated by a high-power microwave generator, comprises a unidirectional element which imposes an appropriate constant load on the generator, and a reflector system constituted by a waveguide D tapped into the output waveguide T of the unidirectional element, said waveguide D being terminated at its free end by a metal plate carrying three quartz rods 10, 11, 12 designed to slide, parallel to the axis of the waveguide D, respectively in three metallic sleeves 13, 14, 15 having a circular shape and dimensioins such that they form cut-off waveguides at the operating frequency of the generator. The free end of each of the sleeves 13, 14, 15 provided with three respective rings 16, 17, 18 of absorber material.

Abstract: A monitoring device transparent to ionizing radiation, designed to measure the orientation, intensity and uniformity of an incident beam, comprises a cylindrical housing forming at least one ionization chamber with one or more ion-collecting electrodes transverse to the housing axis, each electrode being subdivided into a plurality of mutually insulated conductive elements connected to respective amplifiers. The elements of at least one electrode include one or more outer elements surrounding or bracketing one or more inner elements to measure the radiation in a central zone and a peripheral zone. The outputs of the respective amplifiers are additively and subtractively combined in an evaluation circuit.