| Superconducting magnets have become broadly used for cyclotrons due to advantages of compactness and lower operation costs compared to conventional magnets. To gain benefits of higher magnetic fields beyond the 5 tesla cyclotron magnets which are under operation in several laboratories including the MSU/NSCL, a test magnet which can produce fields higher than 8 tesla was constructed. Our goal was to develop the coil construction technique, to use the magnet as a test stand, and to pursue a conversion to a cyclotron in the future.;Using the 8 tesla magnet to generate a broad range of radially flat fields from 2 to 8 tesla, emittance measurements of an internal ion source would be possible in the magnet's center region. Computations were made to yield a possible experimental scheme for the measurement.;An eventual use of the 8 tesla magnet could be a conversion to a cyclotron. In the design study presented in the appendix, the 8 tesla magnet is assumed to accelerate deuterons in a central field of 7.2 tesla. This would yield a deuteron energy of 35 MeV, i.e. a cyclotron K value of 70 MeV. To utilize the maximum field produced by the 8 T magnet (;The basic magnet design has the characteristics of a superconducting isochronous cyclotron. Because of the large magnetic forces in high field coils, the coil design has been intensively studied with computations and experiments. When construction was completed, the magnet proved to produce fields higher than 8 tesla at 4.4 K. Magnet properties such as spring constants of link assemblies and magnetic off-centering forces, magnet inductances, and heat leak to 4 K were measured and compared with computations. Magnetic fields were also measured along a radial line at a fixed angle, and compared to 3-d field calculations made with the TOSCA program. |
