Application of high-temperature superconducting permanent magnets to synchrotron radiation sources

• Main Authors: Takashi Tanaka, Toru Hara, Hideo Kitamura, Rieko Tsuru, Teruhiko Bizen, Xavier Maréchal, Takamitsu Seike
• Format: Article
• Language: English
• Published: American Physical Society 2004-09-01
• Series: Physical Review Special Topics. Accelerators and Beams
• Online Access: http://doi.org/10.1103/PhysRevSTAB.7.090704

A simple scheme for field enhancement in synchrotron radiation sources such as undulators and wigglers is proposed, which is based on the fundamental nature of the superconducting loop where the magnetic flux is preserved. A superconductor ring placed to enclose the magnetic pole works as a kind of permanent magnet. The magnetization is performed by electromagnetic induction brought by the opening movement of the magnetic gap. Since neither additional external power supplies nor current leads are necessary, high-temperature bulk superconductors can easily be implemented in this scheme. Calculations to check the effectiveness of the new concept show that the critical current density of the superconductor is crucial to the performance of the synchrotron radiation sources based on this concept. Experiments were performed to verify the principle of the proposed scheme, which gave promising results to strongly support it.