Berkeley Lab

Goal 1: Developing Nb3Sn to its Fundamental Limits

Explore the performance limits of niobium-tin (Nb3Sn) accelerator magnets with a focus on minimizing the required operating margin and significantly reducing or eliminating training.

Magnets with a small bore or no bore have reached 16 T in the US and recently at CERN. Modeling indicates that this is close to the practical limit for currently available high performance Nb3Sn wire. The remaining challenge is to realize this potential in accelerator quality magnets, both in magnets with small aperture, typical of high energy colliders, and in magnets with larger aperture, to provide background field for HTS inserts. We aim to demonstrate the feasibility of a magnet with a bore field of 16 T (at 90% of the conductor limit) with a bore greater than or equal to 50 mm with two complementary approaches:

These goals will be achieved by focusing on high field dipole development along four elements.

  1. Establishment of a baseline design to demonstrate feasibility of 16 T magnets and the development of higher risk innovative concepts to improve performance and reduce cost.
  2. Feasibility assessment of accelerator magnets based on HTS materials.
  3. A supporting program of science and technology development that serves as the core of the MDP. This component will provide a means of exploring new design concepts, instrumentation, diagnostics and fabrication techniques in a controlled and cost-effective way. The model magnets will serve as platforms for integration of the results of these ongoing activities.
  4. A conductor development program that challenges existing strand and cable performance parameters and is driven by the magnet R&D goals, and which supports these main elements.

The program is focused on transformational magnet technologies, leveraging the significant experience base developed in the magnet programs while incorporating a strong science-based element to address limitations to magnet performance. Success will rely upon a collaborative effort of U.S. national labs, industry and universities that takes maximum advantage of existing infrastruc- ture and expertise at the participating institutions by combining and coordinating intellectual and infrastructure resources.

The work outlined here will advance high-energy physics while increasing our own capabilities in accelerator magnet technology. This will position the U.S. for a leadership position in the development of enabling technology for the next generation of very high energy proton-proton colliders and, in the nearer term, establish a technology base for a possible energy upgrade of the LHC. As an HEP funded Program, its primary focus is on magnets for accelerators, but the generic approach will develop magnet technologies that can be applied to a large variety of applications across the DOE Office of Science and beyond.

usmdp goals