Design and Fabrication of Iron-Dominated Magnets and Cryomodule Magnetic Shielding for the Re-Accelerator Project at MSU

• Published in: IEEE transactions on applied superconductivity Vol. 24; no. 3; pp. 1 - 5
• Main Authors: Chouhan, S. S., Witgen, R., Compton, C., DeKamp, J., Lin, L. Y., Saito, K., Yamazaki, Y., Zeller, A. F.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01-06-2014; Institute of Electrical and Electronics Engineers
• Subjects: Applied sciences; Cavity resonators; Circuit properties; Cryostat; dipole magnet; Electric, optical and optoelectronic circuits; Electrical engineering. Electrical power engineering; Electromagnetic compatibility; Electromagnets; Electronic circuits; Electronic tubes, masers; Electronics; Exact sciences and technology; Information, signal and communications theory; Magnetic hysteresis; Magnetic noise; Magnetic shielding; Oscillators, resonators, synthetizers; quadrupole magnet; Saturation magnetization; Solenoids; Superconducting magnets; superferric; Telecommunications and information theory; Various equipment and components; warm iron; Performance evaluation; Magnetic screen; Linear accelerator; Electromagnetic shielding; Nuclear reaction; Quadrupoles; Hysteresis loop; Cyclotron; Cavity; quadrupole magnet; Dipole; Beam transport; dipole magnet; Magnetic field; warm iron; Resonator; Magnet; Compact design; Magnetic shielding; Solenoid; Residual impurity; Cryostat; superferric; Facility; Low-power electronics; Room temperature
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2013.2288931

The National Superconducting Cyclotron Laboratory at Michigan State University is constructing a rare isotope beam re-accelerator facility, called "ReA." The compact facility will provide unique reaccelerated low-energy rare isotope beams produced by in-flight nuclear reactions and then stopped by interaction with matter. The ReA3 linac beam transport system comprises of room-temperature dipoles, quadrupoles, solenoids, and corrector magnets. The accelerating system of the linac is composed of cryomodules each containing niobium resonators and superconducting solenoids. The performance of the cavity is sensitive to magnetic fields coming mainly from the solenoid fringe field and the residual Earth's field. The 9-T solenoid is shielded with both a return yoke and bucking coils to reduce the magnetic field in the neighboring SRF cavities. The cavities are also equipped with a shield made up of commercially available high permeable material to further reduce the magnetic field on the cavities. Two of the cryomodules are in operation and have demonstrated effective shielding, eliminating the requirement of hysteresis cycling. This paper presents the results of the design of the magnets, fabrication, and status. In addition to the design of the magnetic shield, results of the survey of magnetic field in the cavities are presented.