Secondary Electron Emission Characteristics of Laser Etched Copper at Cryogenic Temperature

In order to reduce the thermal load of the accelerator and improve the beam quality,suppressing the electron cloud effect becomes the basic requirement in the design and construction of future particle accelerators.Secondary electron yield (SEY) is one of the main factors of the electron cloud phenomenon,which represents the ability of secondary electron generation on the surface of materials.Laser etching technology is a method to suppress secondary electron emission by modifying the surface microstructure of the material.It has the advantages of simple operation and high repeatability.In order to evaluate the engineering application potential of laser etching technology,we built a cryogenic secondary electron yield test system.The oxygen-free copper samples were laser etched with different patterns to study the secondary electron emission characteristics of the samples at different temperatures.The scanning electron microscope test results showed that the etched sample surface had a regular gully structure and spherical structure.The SEY on the surface of the material at cryogenic temperature is affected by the interaction of the adsorbed gas layer and the intrinsic properties of the substrate,and the microstructure of the substrate also affects the ability of secondary electron emission.