Development of NbTi planar superconducting undulators at the IHEP

• DOI: 10.3389/fphy.2023.1153005
• Publication Date: 2023-04-05T04:37:26Z
• Authors: Junhao Wei; Xiangchen Yang; Zilin Chen; Xiangzhen Zhang; Xiaojuan Bian; Yuhui Li
• Keywords: Cryostat; Electromagnet

Superconducting undulators (SCUs) have the advantages of generating stronger magnetic field and radiation hardness compared to permanent magnet undulators. Therefore, SCUs are valuable be applied in free-electron lasers (FELs) driven by high-repetition-rate linear accelerators. The Insertion Device Group at Institute High Energy Physics (IHEP) China started an R&D project produce NbTi planar SCU prototypes with 15 mm period length. Several prototypes, including short mock-ups, a 0.5-m-long SCU, 1.5-m-long been successfully produced cryogenic tested. mock-up coils were cooled liquid helium free cryostat quench trained 4 K. maximum current reached 500 A peak exceed 1 T 7 gap. was tested using vertical test system. correction confirmed ability both correcting integrals phase error. not only vertically tested, but also installed operated high over long time. We gap adjustment method reduce error within 9 degrees. development IHEP is introduced this paper detail.