Development of A Modified Quasi-periodic Undulator for HLS

TL;DR

This paper presents a modified quasi-periodic undulator designed for HLS, which effectively reduces harmonic contamination and enhances the suppression of higher harmonics through optimized magnet dimensions and practical verification.

Contribution

A novel modified QPU with optimized magnet dimensions is developed, significantly improving harmonic suppression compared to existing devices.

Findings

3rd harmonic suppression increased by an order of magnitude

Effective elimination of high harmonics contamination

Successful design, measurement, and commissioning of the device

Abstract

A modified quasi periodic undulator (QPU) is developed and to be installed at Hefei Light Source (HLS).Magnet dimensions optimization is applied. High harmonics contamination is eliminated from the fundamental emission effectively according to the field tests. The depression ratio of 3rd harmonic is increased by an order of magnitude than the current device with other harmonics well reduced simultaneously. The significance of the modification measure is verified practically. The design, measurement and commissioning of the device is described.