Enhancing the Radiation Resistance of Undulator Permanent Magnets by Tilting the Easy Axis of Magnetization
Phys. Rev. Lett. 121, 124801 – Published 17 September, 2018
DOI: https://doi.org/10.1103/PhysRevLett.121.124801
Abstract
The undulator is a magnetic device usually consisting of a series of rare-earth permanent magnets (REPMs) arranged to generate a sinusoidal magnetic field, and is installed in synchrotron radiation and free electron laser facilities to periodically deflect high-energy electrons. Because the undulator is operated under a high-radiation environment, it is important to take possible measures to avoid the quality degradation, in particular the radiation damage of REPMs. We present a simple scheme to enhance the radiation resistance of REPMs in undulators, in which the easy axis of each REPM is tilted by 45°. Experimental studies have revealed that the radiation resistance of REPMs in this configuration is enhanced by an order of magnitude compared to that in the conventional undulator.
