Fabrication of a Curved-Canted-Cosine-Theta (CCCT) Dipole at CERN

Canted Cosine Theta (CCT) magnet is an interesting design for compact accelerators or gantry systems for hadrontherapy. It offers great flexibility in generating complex field harmonics in straight and curved configurations while remaining compact. The Fusillo project based at CERN aims to design, build, and test a Nb-Ti curved CCT dipole demonstrator generating 3 T at 4.5 K in a large aperture of 236 mm, bent over 90° with a small bending radius of 1 m, and multi-harmonic field features to correct for the curvature. In this paper, we describe the fabrication process, the winding and the assembly of a Fusillo demonstrator that at present is being cold tested in liquid helium.