Open AccessDevelopment and magnetic field measurement of a 0.5‐m‐long superconducting undulator at IHEP
Author(s) -
Wei Junhao,
Li Yuhui,
Yang Xiangchen,
Chen Zilin,
Zhang Xiangzhen,
Bian Xiaojuan
Publication year - 2022
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s1600577522006166
Subject(s) - undulator , magnetic field , physics , superconductivity , magnet , optics , particle accelerator , superconducting magnet , beam (structure) , condensed matter physics , quantum mechanics
Undulators are important devices for accelerator‐based light sources whose magnetic field quality determines the photon beam performance. Superconducting‐type undulators have been developing rapidly in recent years around the world. The insertion device group at the Institute of High Energy Physics (IHEP) in China started an R&D project to develop prototypes of superconducting undulators (SCUs). A half‐meter‐long planar SCU has been produced recently. The SCU was designed based on the simulation program OPERA‐3D giving a period length of 15 mm and a gap of 7 mm. This prototype was manufactured and fabricated precisely, and was then tested by vertically submerging in liquid helium in a Dewar. After quench training several times, the maximum current in the main coils reached 480 A. The magnetic field was measured by Hall probes mounted on a sledge in the middle of the undulator gap. The peak magnetic field reached 1 T. The measurement results indicate that correction coils with suitable current can not only optimize the magnetic first and second integrals but also reduce the phase error, which is expected by design.