Research and development of fundamental technologies for accelerator magnets using high Tc superconductors

The progress of a project on the research and development of fundamental technologies for accelerator magnets using high Tc superconductors (HTS) is reported. The aim of the project is to establish technologies for cryo-cooler-cooled HTS accelerator magnets wound with coated conductors. At the first stage of the project, the conceptual design study of accelerators was carried out, and the coils of the HTS magnets which are compatible with these accelerators were designed successfully. The required winding technologies were clarified through designing the coils, and the R&D of winding technologies for coils with three-dimensional shape and those with negative bend are in progress. The influence of the tape magnetization, that is, the shielding current on the wide face of coated conductor, on the field quality of magnets was studied.

► We designed accelerator magnets using coated conductors which are compatible with accelerator designs.
► A three-dimensional coil and a negative-bend coil were fabricated and were tested in LN2 to show good voltage–current characteristics.
► The influence of tape magnetization on field quality was evaluated by numerical electromagnetic field analyses.