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arXiv · 2302.04940

Conceptual design of 20 T hybrid accelerator dipole magnets

P. Ferracin·G. Ambrosio·M. Anerella·D. Arbelaez·L. Brouwer·E. Barzi·L. Cooley·J. Cozzolino·L. Garcia Fajardo·R. Gupta·M. Juchno·V. V. Kashikhin·F. Kurian·V. Marinozzi·I. Novitski·E. Rochepault·J. Stern·G. Vallone·B. Yahia·A. V. Zlobin
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Abstract

Hybrid magnets are currently under consideration as an economically viable option towards 20 T dipole magnets for next generation of particle accelerators. In these magnets, High Temperature Superconducting (HTS) materials are used in the high field part of the coil with so-called insert coils, and Low Temperature Superconductors (LTS) like Nb3Sn and Nb-Ti superconductors are used in the lower field region with so-called outsert coils. The attractiveness of the hybrid option lays on the fact that, on the one hand, the 20 T field level is beyond the Nb3Sn practical limits of 15-16 T for accelerator magnets and can be achieved only via HTS materials; on the other hand, the high cost of HTS superconductors compared to LTS superconductors makes it advantageous exploring a hybrid approach, where the HTS portion of the coil is minimized. We present in this paper an overview of different design options aimed at generating 20 T field in a 50 mm clear aperture. The coil layouts investigated include the Cos-theta design (CT), with its variations to reduce the conductor peak stress, namely the Canted Cos-theta design (CCT) and the Stress Management Cos-theta design (SMCT), and, in addition, the Block-type design (BL) including a form of stress management and the Common-Coil design (CC). Results from a magnetic and mechanical analysis are discussed, with particular focus on the comparison between the different options regarding quantity of superconducting material, field quality, conductor peak stress, and quench protection.

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P. Ferracin, G. Ambrosio, M. Anerella, D. Arbelaez, L. Brouwer, E. Barzi, L. Cooley, J. Cozzolino, L. Garcia Fajardo, R. Gupta, M. Juchno, V. V. Kashikhin, F. Kurian, V. Marinozzi, I. Novitski, E. Rochepault, J. Stern, G. Vallone, B. Yahia, A. V. Zlobin. 2023-02-09. Conceptual design of 20 T hybrid accelerator dipole magnets. https://doi.org/10.1109/tasc.2023.3250382

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