Towards 20 T Hybrid Accelerator Dipole Magnets

TL;DR

This paper explores the design of 20 Tesla hybrid dipole magnets for particle accelerators, combining Nb3Sn and high-temperature superconductors to surpass current magnetic field limits.

Contribution

It presents preliminary conceptual designs and compares different coil layouts for hybrid magnets using finite element models.

Findings

Compared three main magnet layouts: cos-theta, block, and common-coil.

Analyzed stress management options for high-field hybrid magnets.

Provided initial design parameters for 20 T hybrid dipole magnets.

Abstract

The most effective way to achieve very high collision energies in a circular particle accelerator is to maximize the field strength of the main bending dipoles. In dipole magnets using Nb-Ti superconductor the practical field limit is considered to be 8-9 T. When Nb3Sn superconductor material is utilized, a field level of 15-16 T can be achieved. To further push the magnetic field beyond the Nb3Sn limits, High Temperature Superconductors (HTS) need to be considered in the magnet design. The most promising HTS materials for particle accelerator magnets are Bi2212 and REBCO. However, their outstanding performance comes with a significantly higher cost. Therefore, an economically viable option towards 20 T dipole magnets could consist in an hybrid solution, where both HTS and Nb3Sn materials are used. We discuss in this paper preliminary conceptual designs of various 20 T hybrid magnet concepts. After the definition of the overall design criteria, the coil dimensions and parameters are investigated with finite element models based on simple sector coils. Preliminary 2D cross-section computation results are then presented and three main layouts compared: cos-theta, block, and common-coil. Both traditional designs and more advanced stress-management options are considered.