As part of the LOI (Low Output Impedance amplifier) collaboration involving RAL, ANL and KEK, an opportunity arose for a member of the ISIS RF Group to work with our colleagues in Japan during the commissioning of their ambitious new particle accelerator and neutron source.
The J-Parc facility, just entering it's first phases of full operation, is designed to allow a large variety of physics to be conducted using a single proton driver. A high current linear accelerator is used for both nuclear physics research and feeding a booster synchrotron ring, which in turn feeds a neutron spallation facility and a high energy physics main ring. The source for the T2K (Tokai to Kamioka) neutrino experiment is also fed by the accelerator. Research conducted at the lab will allow improve our knowledge of the universe, as well as help develop new materials and medicines back on Earth.
Rob Mathieson of the ISIS Synchrotron RF Group spent a month in Japan assisting and learning from the J-Parc Ring RF Group during the testing phase of some of their new RF equipment. Work concentrated on the continuing development of FineMet magnetic alloy cavities, which allow higher field gradients for accelerating particles and hence require much smaller RF sections. This could be particularly useful for applications where space is limited, such as small scale accelerators used in hospitals for isotope production and hadron therapies. Unfortunately, FineMet is a relatively new material for use in accelerators, and while it's electrical properties are well suited to the task, the problems associated with it's mechanical and material properties require much ingenuity to solve. Rob participated in the 300 hour operational testing of a new main ring cavity, and was also invited to visit the Toshiba Research & Development factory where the cavities are constructed.
It is hoped that J-Parc and ISIS can continue to benefit from such close collaborations in the future.