2–5 Sept 2025
Urumqi, Xinjiang, China
Asia/Shanghai timezone

Modeling and Optimization of Transverse Trapped-Mode Impedance for In-Vacuum Undulators of HALF

THP21
4 Sept 2025, 18:55
1h 35m
Urumqi, Xinjiang, China

Urumqi, Xinjiang, China

Poster Presentation MC2: Beam Dynamics and EM Fields Poster Session

Speaker

Haiyan Yao (University of Science and Technology of China)

Description

The in-vacuum undulator (IVU) exhibits exceptionally strong trapped-mode impedance due to its distinctive ridge-loaded waveguide structure and narrow magnetic gap design, which may lead to beam instability issues. This study primarily use the CST wakefield solver to investigate the trapped-mode impedance of the IVUs of the Hefei Advanced Light Facility (HALF). The trapped-mode impedance in the vertical direction is evaluated for both structures, with and without pump ports. Based on the impedance results, two mitigation strategies are proposed: ferrite damping and transition section optimization. Simulation results demonstrate that both strategies effectively reduce the impedance, with the transition section optimization strategy showing superior suppression performance.

I have read and accept the Privacy Policy Statement Yes

Author

Haiyan Yao (University of Science and Technology of China)

Co-authors

Tianlong He (University of Science and Technology of China) Weiwei Li (University of Science and Technology of China) Mr Xiaoyu Liu (University of Science and Technology of China) Zhenghe Bai (University of Science and Technology of China) 鑫 黄 (National Synchrotron Radiation Laboratory)

Presentation materials

There are no materials yet.