Abstract: An NMR measuring arrangement (20) includes a cryostat (1), a superconducting magnet coil system (2) and an NMR probe (3). The cryostat has an evacuated vacuum container (5) and forms a bore (10). A wall (12) of the bore delimits the vacuum container. The cryostat forms only one evacuated gap (13) in a space (18) between the magnet coil system and the wall of the bore. At least a segment of the wall of the bore is thermally coupled to a heat sink of the cryostat. As a result, the NMR measurement arrangement provides more precise NMR measurements (in particular with a higher spectral resolution and/or a higher signal-to-noise ratio) on measurement samples.

Abstract: A magnetic field shielding system includes a first stage superconducting coil and a second stage superconducting coil. The first stage superconducting coil and the second stage superconducting coil are coaxial, coplanar and electrically connected in series to form a closed loop; the first stage superconducting coil has a first radius R1, the second stage superconducting coil has a second radius R2, and R1>R2; a radius ratio ? between the first radius R1 and the second radius R2 is: ?=R1/R2; the first stage superconducting coil has N1 turns; the second stage superconducting coil has N2 turns; a turns ratio ? between N1 and N2 is: ?=N1/N2; and the radius ratio ? satisfies: ??2; the turns ratio ? satisfies: 0.01???20.

Abstract: Provided is a method of manufacturing a superconducting accelerator cavity in which a plurality of half cells having opening portions (equator portions and iris portions) at both ends thereof in an axial direction are placed one after another in the axial direction, contact portions where the corresponding opening portions come into contact with each other are joined by welding, and thus, a superconducting accelerator cavity is manufactured, the half cells to be joined are arranged so that the axial direction thereof extends in a vertical direction; and concave portions that are concave towards an outer side are also formed at inner circumferential surfaces located below the contact portions of the half cells positioned at a bottom; and the contact portions are joined from outside by penetration welding.

Abstract: The invention relates to a magnet structure for a superconducting isochronous cyclotron for use in particle therapy. The cyclotron according to the invention is using two sets of three or more superconducting sector coil elements for generating an azimuthally varying magnetic field across the acceleration region. In this way, high-field (e.g. above 4 T) isochronous cyclotrons are provided which do not suffer the problem of a low flutter amplitude.

Abstract: An apparatus and process for the production of a niobium cavity exhibiting high quality factors at high gradients is provided. The apparatus comprises a first chamber positioned within a second chamber, an RF generator and vacuum pumping systems. The process comprises placing the niobium cavity in a first chamber of the apparatus; thermally treating the cavity by high temperature in the first chamber while maintaining high vacuum in the first and second chambers; and applying a passivating thin film layer to a surface of the cavity in the presence of a gaseous mixture and an RF field. Further a niobium cavity exhibiting high quality factors at high gradients produced by the method of the invention is provided.

Abstract: A superconducting accelerating cavity production method with which a high-quality superconducting accelerating cavity can be produced with a compact device configuration and at low cost. The method of producing a superconducting accelerating cavity (1) includes arranging, in an axial direction (L), a plurality of half-cells (5) having openings at both ends in the axial direction and joining the openings to one another by welding. The half-cells (5) are joined by welding with a laser beam from the inside of the superconducting accelerating cavity (1) in which a vacuum atmosphere is created.

Abstract: A cyclotron for ion acceleration is magnetically shielded during ion acceleration by passing electrical current in the same direction through both the first and second superconducting primary coils. A first magnetic-field-shielding coil is on the same side of the mid plane as the first superconducting primary coil, while a second magnetic-field-shielding coil is on the same side of the midplane as the second superconducting primary coil and beyond the outer radius of the second superconducting primary coil. Electrical current is also passed through the magnetic-field-shielding coils in a direction opposite to the direction in which electrical current is passed through the superconducting primary coils and generates a canceling magnetic field that reduces the magnetic field generated at radii from the central axis beyond the magnetic-field-shielding coils.

Abstract: Provided is a superconducting accelerator cavity and a method thereof with which product reliability can be enhanced and manufacturing costs can be reduced. A method of manufacturing a superconducting accelerator cavity includes a beam-pipe forming stage of forming a beam pipe by processing a superconducting material into a tube shape; an end-plate joining stage of joining, by welding, an inner circumferential surface of an end plate formed in a shape of a ring that forms an end of a jacket, which accommodates coolant, to an outer circumferential portion of an end in the beam pipe formed in the beam-pipe forming stage; and an end-cell joining stage of joining, by welding, an iris portion of an end cell, which is formed of a superconducting material in a shape of a ring so as to form a cavity portion, to an inner circumferential portion of the end of the beam pipe.

Abstract: Provided is a superconducting accelerator cavity and a method thereof with which product reliability can be enhanced and manufacturing costs can be reduced. A method of manufacturing a superconducting accelerator cavity includes a beam-pipe forming stage of forming a beam pipe by processing a superconducting material into a tube shape; an end-plate joining stage of joining, by welding, an inner circumferential surface of an end plate formed in a shape of a ring that forms an end of a jacket, which accommodates coolant, to an outer circumferential portion of an end in the beam pipe formed in the beam-pipe forming stage; and an end-cell joining stage of joining, by welding, an iris portion of an end cell, which is formed of a superconducting material in a shape of a ring so as to form a cavity portion, to an inner circumferential portion of the end of the beam pipe.

Abstract: The present invention is a method of enhancing efficacy of electrical apparatuses by using the augmented velocity electrons.

Abstract: Disclosed is a termination that connects high temperature superconducting (HTS) cable immersed in pressurized liquid nitrogen to high voltage and neutral (shield) external bushings at ambient temperature and pressure. The termination consists of a splice between the HTS power (inner) and shield (outer) conductors and concentric copper pipes which are the conductors in the termination. There is also a transition from the dielectric tape insulator used in the HTS cable to the insulators used between and around the copper pipe conductors in the termination. At the warm end of the termination the copper pipes are connected via copper braided straps to the conventional warm external bushings which have low thermal stresses. This termination allows for a natural temperature gradient in the copper pipe conductors inside the termination which enables the controlled flashing of the pressurized liquid coolant (nitrogen) to the gaseous state.

Abstract: Periodic and pseudo-periodic slow wave structures comprising a plurality of adjacent sections, each section comprising a dielectric ring in contact with a disk coated with high temperature superconducting thin film, having coupling between the sections and tunable phase velocity for use in particle accelerators and traveling wave tubes are disclosed.

Abstract: A cathode for a secondary emission structure comprised of a superconductive material is described. In one embodiment the cathode comprises a layer of a superconductive material such as yttrium barium cupric oxide, or rare earth substituted neodymium cupric oxides. The layer may be bonded to a metal electrode or preferably the cathode consist of a superconductive or conductive oxide. The use of a superconductive material provides a cathode having suitable secondary emission characteristics and, furthermore, which being conductive at room temperatures, as well as, temperatures of operation of the cathode, obviating the need for a use of a very thin film of a secondary emission material.