Advanced Design for the WIQ Magnet With Steering Corrector Function

Journal Article · Tue Feb 11 00:00:00 EST 2025 · IEEE Transactions on Applied Superconductivity

DOI:https://doi.org/10.1109/TASC.2025.3541022· OSTI ID:3001572

Du, Xiaoji ^[1]; Choi, Yoonhyuck ^[1]; Portillo, Mauricio ^[1]; Greene, David ^[1]; Wenstrom, John ^[1]; Nguyen, Hai ^[1]; Zhang, Danlu ^[1]; Jones, Christopher ^[1]; Sherrill, Bradley M. ^[1]; Xu, Ting ^[1]

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1. Michigan State University, East Lansing, MI (United States)

The Facility for Rare Isotopes Beams (FRIB) delivers heavy-ion primary beams at energies of up to 300 MeV/u at 10 kW of beam power to generate rare isotope beams for experiments and will eventually operate at beam power of 400 kW. The preseprator of the Advanced Rare Isotope Separator (ARIS) is equipped with six warm-iron quadrupole (WIQ) singlets and two dipoles integrated right after the production target. They have a compact structure and operate in a high radiation vacuum environment within a hot cell having remote handling capabilities for installation and maintenance. Due to asymmetry with respect to the quadrupole poles, nested sextupole excitations in WIQs induce vertical dipoles that offset the centroid trajectory; Magnet misalignments also result in trajectory offsets. Such offsets degrade separator performance but can be minimized by changing the current distribution on sextupole and octupole coils. In this work, we show how modifications to the WIQ coil design can allow superimposed dipole fields to be included to the octupole and sextupole windings, as well as addition of dipole components by splitting coil currents over groups with separator power supplies. Adjusting the group currents can cancel the sextupole-induced vertical dipole component which can be as high as 0.012 Tm. Octupole coil changes may superimpose a horizontal dipole integrated strength as high as 0.0332 Tm. Unwanted higher harmonics induced as a side effect of the new design are kept to a minimum such that separator performance is preserved as much as possible.

• Research Organization: Michigan State University, East Lansing, MI (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: SC0023633
• OSTI ID: 3001572
• Journal Information: IEEE Transactions on Applied Superconductivity, Journal Name: IEEE Transactions on Applied Superconductivity Journal Issue: 5 Vol. 35; ISSN 1051-8223; ISSN 2378-7074; ISSN 1558-2515
• Publisher: Institute of Electrical and Electronics Engineers (IEEE)
• Country of Publication: United States
• Language: English

Related Subjects

Accelerator magnets
magnet design and analysis techniques
magnetic field quality