Speaker
Description
In this work, we present the design of a combined-function Canted-Cosine-Theta (CCT) accelerator magnet with an elliptic aperture and report progress on the fabrication of a NbTi demonstrator magnet. This unique bore shape is desired for fixed-field accelerators to accommodate horizontal orbit offset between beams of different energy. We first share the magnetic and mechanical design of a two-layer CCT magnet based on NbTi Rutherford cables, with a target field of 5 T at 4.2 K. Analytic and numerical methods are employed to optimize the coil winding path to produce the desired combination of dipole and quadrupole fields. The iron shape and coil path are further optimized using a 3D magnetic model to reduce the undesired higher-order harmonics resulting from iron saturation. Stress analysis is carried out with periodic 3D and full 3D models to ensure mechanical robustness. We then discuss the unique advantages and challenges when developing fabrication procedures using subscale prototypes. Finally, we report the status of layer fabrication and assembly of the 0.6 m long demonstrator magnet.