Design and Test of the Super-Ferric Dipole Magnet for HIAF-HFRS

HIAF (High Intensity heavy ion Accelerator Facility) is a new generation heavy ion accelerator under construction in China. The HFRS (FRagment Separator of HIAF) is a fragment separator and also a transfer-line between the Booster Ring and the Spectrometer ring. HFRS magnet system is composed of 11 superconducting dipoles and 13 sets of triplets. The dipole magnets adopt a super-ferric scheme. The requirement for the dipole magnets is a large acceptance at moderate fields, which can be fulfilled by super-ferric magnets with wide apertures. The magnetic field ranges from 0.2 T to 1.6 T with a bending radius of 15.7 m and a bending angle of 10°. A homogeneous dipole magnet field shape is required in the good field region of x ±160; y ±70 mm. This paper presents a detailed design and optimization of the magnet based on a multi-parametric model. The integral field homogeneity is optimized by an automatic chamfering algorithm. According to the installation conditions of the HIAF-HFRS, the magnet adopts a block processing and assembly method, which is manufactured and assembled by 14 blocks. The first set of the magnets has been completed and tested, and the test results are better than the design indicators.