Force-compensating spring modules of self-contained type for small phase error performance in in-vacuum undulators

Autor: Shinsaku Mizumoto, Jui-Che Huang, Tsutomu Kohda, Chih-Sheng Yang, Chin-Kang Yang, Hideo Kitamura, Ching-Shiang Hwang, Cheng-Hsing Chang
Rok vydání: 2021
Předmět:
Zdroj: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 1013:165650
ISSN: 0168-9002
DOI: 10.1016/j.nima.2021.165650
Popis: In an in-vacuum undulator, the dynamic phase error, which is a kind of systematic phase errors, is increased because the out-of-vacuum girder is deformed with a strong magnetic force. As a result, the spectral performance of synchrotron radiation is deteriorated. A recommended solution for a problem of this kind is to adopt a spring system to compensate the magnetic force, but a conventional spring system has a problem in that the mechanical frame of the undulator is deformed by a reaction force from the springs. The new force-compensating spring module shown in this paper is a self-contained type that can treat the spring reaction force within the module, therefore, the side effects of the spring operation can be minimized. Three in-vacuum undulators with a length of 2–4 m are equipped with the spring modules of new type, so a small rms phase error of 1.7°–2.2° is obtained under the highest magnetic force at the minimum gap.
Databáze: OpenAIRE