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arXiv · 2405.20105

The first superconducting final focus quadrupole prototype of the FCC-ee study

A. Thabuis·M. Koratzinos·G. Kirby·M. Liebsch·C. Petrone
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Abstract

A single aperture Canted-Cosine-Theta (CCT) quadrupole magnet, made of NbTi superconductors, has been developed for the final focus region of the FCC-ee study. The conductor layout is optimised to mitigate edge effects on one of the two sides of the magnet that typically lead to undesired higher-order multipoles. Experimental results of a prototype, including paraffin wax impregnation and cryogenic temperature measurements, are presented. The magnet exhibits no training behaviour, surpassing the nominal current during the initial ramp. Field quality is excellent, with higher-order multipoles below $1\times 10^{-4}$ units, consistent with simulations and room temperature tests. These findings confirm the potential of superconducting CCT magnets to offer compact solutions for applications demanding stringent field quality.

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A. Thabuis, M. Koratzinos, G. Kirby, M. Liebsch, C. Petrone. 2024-05-30. The first superconducting final focus quadrupole prototype of the FCC-ee study. https://doi.org/10.18429/jacow-ipac2024-weps65

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