Abstract: A cryostat assembly having an outer vessel within which is provided substantially upright inner vessel for containing an item, such as an electromagnet, to be cooled. The inner vessel is suspended from the outer vessel by a number of low thermal conductivity support members secured at one end to points on the outer vessel corresponding to the height of the center of gravity of the assembly and an item in use and at the other end to the inner vessel at points not higher than the said points on the outer vessel.

Abstract: An apparatus for monitoring characteristics of rock cores using NMR. The apparatus is provided with a clad permanent magnet for generating a magnetic field having a saddle profile. The magnetic field is sufficiently uniform within a working volume to enable an NMR experiment to be performed. Rock cores are conveyed along a path about which the magnet is arranged. The cores pass through the working volume of the magnetic field orthogonally to the saddle profile of the magnetic field. An NMR experiment to monitor oil bearing rock characteristics, such as porosity is carried out on a portion of the rock core within the working volume.

Abstract: In a proton/neutron source incorporating a cyclotron, in particular a superconducting cyclotron having a cylindrical superconducting magnet incorporating superconducting magnetic coils associated with pole pieces, a stream of ionized particles, such as H.sup.- particles, is continuously injected into the center of the cyclotron beam space and is accelerated outwards in a spiral path under the combined effect of the magnetic field from the superconducting magnet, and RF energization applied to sector-shaped electrodes. When the particles reach the required energy, they are removed from the spiral path by septa electrodes, and are passed across a proton storage ring in a path of rapidly increasing radius under the influence of the falling magnetic field of the superconducting magnets.

Abstract: A cyclotron having a cylindrical superconducting magnet which generates an axial magnetic field and has a central opening or chamber of substantially circular cross-section. The accelerating beam space is located in this chamber lying normal to the axis of the magnetic field. The azimuth variation of magnetic field as well as the isochronous radial variation of magnetic field required to control the orbiting of the ion beam in the beam space, are provided by ferro-magnetic pole pieces located in the axial chamber, which interact with the magnetic field to cause the required field variations. Interposed between the pole pieces are resonant frequency members which provide the radio frequency energization to accelerate the ion beam around the beam space. Having the whole of the central chamber free for top and bottom access enables the pole pieces to be given an efficient design shape.