Outline of TARN-II and the magnet

Recently, among accelerators, the necessity of heavy ion synchrotrons has increased, and in the Institute of Nuclear Study, University of Tokyo, a heavy ion synchrotron TARN-2 (Test Accumulation Ring for Numatron) was planned, and a part of its electromagnets has been manufactured for trial. This electromagnet is a deflecting electromagnet for the heavy ion synchrotron, and it is characterized by the magnetic field as high as 1.8 T in order to make the synchrotron small. For attaining this feature, the structure of magnetic poles by optimizing round edge and the H-shaped structure for reducing the displacement due to magnetic force and reducing the weight were adopted, and the manufacture with high dimensional accuracy was carried out. As the shop test, the measurement of dimensions, resistance inductance and the pressure loss of cooling water, and coil insulation test were performed, and the excellent performance was confirmed. The objective of the TARN-2 is to develop the future research on nuclear physics and to establish the technology for practical heavy ion accelerators. Beam is injected from the existing SF cyclotron to the synchrotron, and protons are accelerated to 1300 MeV. (Kako, I.)