The RIKEN Nishina Center began construction of the Radioactive Isotope Beam Factory (RIBF) in 1997, and succeeded in commissioning the beam of its accelerator complex at the end of 2006. The world’s first superconducting ring cyclotron (SRC) is the final booster in the RIBF accelerator complex. It is capable of accelerating all-element heavy ions to a speed of about 70% of the speed of light. Assembly of the superconducting sector magnets was completed in August 2005. The superconducting coils were successfully cooled down and excited for tests on many operational aspects: magnetic force, coil protection and quality of magnetic field, showing that they work as designed. After a series of tests the other components were installed and tested under stray fields from the sector magnets. Local magnetic shields were supplied for the components that could not work under the stray fields. After setting the beam vacuum and radio frequency, beam commissioning started. The first beam was extracted at the end of 2006, and the first uranium beam was extracted in March 2007.
The research and development of superconductor motors using high-temperature superconductors is being carried out all over the world for the purpose of miniaturizing and efficiently upgrading motors. However, the practical applications of the motors have not been covered yet. In this explanation, the elements which constitute the high-temperature superconductor motor are described; namely, a high-temperature superconductor, cooling, and a synchronous motor .Specific examples of high-temperature superconductor motors for low-speed applications are also described.
Flux pinning interaction originates from the variation in the energy of a flux line during its displacement across inhomogeneous regions called pinning centers such as normal precipitates or grain boundaries. The flux pinning mechanism is classified according to the dominant energy involved in the interaction. Normal precipitates and grain boundaries work as strong pinning centers through a condensation energy interaction. The field-induced pinning resulting from a weak superconducting region is also classified in the condensation energy interaction. Magnetic interaction and kinetic interaction are also introduced. The pinning mechanism of artificially introduced Nb into Nb-Ti is considered to be a kinetic energy interaction.