17–22 May 2026
C.I.D
Europe/Zurich timezone

Development of in-situ field measurement system for Korea-4GSR in-vacuum undulators

TUP2716
19 May 2026, 16:00
2h
C.I.D

C.I.D

Deauville, France
Board: Tuesday wine: WD15
Poster Presentation MC2.T15: Photon sources: Undulators and Wigglers Poster session

Speaker

Geonhee Choi (Korea Basic Science Institute)

Description

Precise magnetic-field characterization of in-vacuum undulators is essential for achieving stable beam dynamics in synchrotron light sources. This work presents an in-situ measurement platform that integrates a SAFALI-based Hall probe scanner with a stretched-wire measurement system. The Hall probe unit measures the local magnetic-field distribution along the undulator, achieving micrometer-level positioning accuracy through laser interferometry and optical feedback. In parallel, the stretched-wire system enables reliable determination of the first and second magnetic-field integrals. To minimize magnetic distortion, most mechanical structures are fabricated from low-permeability materials. The system is designed to characterize in-vacuum undulators with magnetic lengths of up to 3 m, allowing comprehensive field mapping without removing the vacuum chamber. The integrated platform is currently under construction for application to in-vacuum undulators at the Korea-4GSR Facility and is expected to improve phase-error reproducibility while providing direct verification of undulator magnetic performance.

Paper status Proceeding files received

Authors

Beom Jun Kim (Pohang Accelerator Laboratory) Geonhee Choi (Korea Basic Science Institute) Dr Yoon Geol Choi (Pohang University of Science and Technology)

Co-authors

Dong Eon Kim (Pohang Accelerator Laboratory) Garam Hahn (Pohang Accelerator Laboratory) Woulwoo Lee (Pohang Accelerator Laboratory) YoungGyu Jung (Pohang Accelerator Laboratory)

Presentation materials