Development of Fast Scanning Magnets and Their Power Supply for Particle Therapy

• Published in: IEEE transactions on applied superconductivity Vol. 24; no. 3; pp. 1 - 4
• Main Authors: Furukawa, T., Shirai, T., Inaniwa, T., Sato, S., Takeshita, E., Mizushima, K., Hara, Y., Noda, K., Kakutani, N., Kanai, Y., Iseki, Y., Hirata, Y., Yamazaki, C.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01.06.2014; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Beams (radiation); Commissioning; Electrical engineering. Electrical power engineering; Electromagnets; Electronic equipment and fabrication. Passive components, printed wiring boards, connectics; Electronics; Exact sciences and technology; Ion beams; Irradiation; Magnetic field measurement; Magnetic separation; Magnetostatics; Magnets; Particle therapy; Power electronics, power supplies; Power supplies; Radiation effects; Ramps; Scanning; scanning delivery; Temperature measurement; Various equipment and components; Performance evaluation; Magnet; scanning delivery; Thermal behavior; Ion beam; Heavy ion; Power supply; Power electronics; Implementation; Commissioning; Dynamic measurement; Beam scanners; Particle therapy; Dipole; Irradiation; Ion accelerators; Delay time; Facility; Heating up
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2013.2281355

At the Heavy Ion Medical Accelerator in Chiba (HIMAC), more than 8000 patients have been successfully treated by carbon ion beams since 1994. The successful results of treatments have led us to construct a new treatment facility equipped with a 3-D pencil beam scanning irradiation system. For the implementation of this irradiation technique, we developed a fast scanning magnet and its power supply, which are required to have field ramp rate of more than 250 T/s. The scanning magnets set at the entrance of the irradiation system are two dipole magnets to scan the beam in both horizontal and vertical directions and used to form the irradiation field to be tumor shape. Before the installation, performance test including both static and dynamic field measurement was carried out. Severe delay of the field and temperature rise were not observed as expected. Measured field ramp rate reached up to 300 T/s. After the installation, we verified the accuracy and stability of the scanned ion beam through the commissioning with the beam. As a successful result of the commissioning, treatment using the new scanning system was started in 2011.