Influence of the photon beam position on incident SR intensity at the SXMCD endstation  

作　　者：郭玉献 徐彭寿 

机构地区：[1]Department of Mathematics & Physics, Anhui University of Architecture [2]National Synchrotron Radiation Laboratory, University of Science & Technology of China

出　　处：《Chinese Physics C》2013年第12期114-118,共5页中国物理C（英文版）

基　　金：Supported by National Natural Science Foundation of China(21271007,10274073);Post-doctoral Research Start-up Funding of Anhui University of Architecture(K02553)

摘　　要：A small fluctuation of the photon beam position will affect the intensity and polarization characteristics of synchrotron radiation （SR） when it enters an endstation through the related beamline. In this paper, by changing the electron orbit equilibrium position in the vertical direction, we have measured the corresponding changes in the absorption strength of the SR with a gold mesh in different chopper aperture positions. It is found that for three aperture positions, the absorption intensity of the gold mesh shows a good Gaussian distribution as the photon beam position moves, while the ratio of the SR intensity passing through the upper and lower apertures shows a monotonous variation. This suggests a new method for estimating the circular polarization degree of SR originating from the bending magnet based on our current measurement.A small fluctuation of the photon beam position will affect the intensity and polarization characteristics of synchrotron radiation （SR） when it enters an endstation through the related beamline. In this paper, by changing the electron orbit equilibrium position in the vertical direction, we have measured the corresponding changes in the absorption strength of the SR with a gold mesh in different chopper aperture positions. It is found that for three aperture positions, the absorption intensity of the gold mesh shows a good Gaussian distribution as the photon beam position moves, while the ratio of the SR intensity passing through the upper and lower apertures shows a monotonous variation. This suggests a new method for estimating the circular polarization degree of SR originating from the bending magnet based on our current measurement.

关 键 词：polarization degree measurement CHOPPER synchronous radiation （SR） X-ray magnetic circular dichro-ism （XMCD） X-ray absorption 

分 类 号：O434.1[机械工程—光学工程]