Design of B2PF: A Large Aperture Nb-Ti Dipole Magnet for the Electron-Ion Collider

Journal Article · 05 February 2025 · IEEE Transactions on Applied Superconductivity

DOI: https://doi.org/10.1109/tasc.2025.3538641 · OSTI ID:2529411

Brouwer, L.  ^[1]; Messe, C.  ^[1]; Amm, K. ^[2]; Bai, Y.  ^[2]; Berg, J. S.  ^[2]; Drees, A. ^[2]; Ferracin, P.  ^[1]; Hamdi, K. ^[2]; Prestemon, S.  ^[1]; Sabbi, G.  ^[1]; Vallone, G.  ^[1]; Witte, H.  ^[2]

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1. Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
2. Brookhaven National Laboratory (BNL), Upton, NY (United States)

Here, we present the initial design of the matching dipole B2PF, a large aperture cosine-theta magnet for the Electron-Ion Collider (EIC). First we share an optimized 2D magnet cross-section based on a double-layer design with Nb-Ti Rutherford cable. This cross-section is optimized to meet the required field quality in the 120 mm coil aperture both at the nominal operating current and considering iron saturation effects during the ramp. Next, we share a first design of the 3D coil ends optimized for windability, field quality, and minimizing the conductor peak field. Based on the resulting peak field, we evaluate the short-sample margin of the design for an operating target of 6.3 T dipole field at 1.9 K. Finally, we share an initial mechanical design study which utilizes a key-and-bladder support structure capable of adjusting magnet preload.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• Grant/Contract Number: SC0012704
• OSTI ID: 2529411
• Report Number(s): BNL--227661-2025-JAAM
• Journal Information: IEEE Transactions on Applied Superconductivity, Journal Name: IEEE Transactions on Applied Superconductivity Journal Issue: 5 Vol. 35; ISSN 1051-8223
• Publisher: IEEECopyright Statement
• Country of Publication: United States
• Language: English