In-vacuum X-ray helical undulator for high flux beamline at SPring-8
In-vacuum X-ray helical undulator for high flux beamline at SPring-8
复制标题
SPring-8 用于高通量光束线的真空 X 射线螺旋波荡器
DOI：
10.1016/s0168-9002(01)00265-0
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发表时间：
2001
影响因子：
1.4
通讯作者：
H. Kitamura
中科院分区：
文献类型：
--
作者：
T. Hara;Takashi Tanaka;T. Seike;T. Bizen;X. Maréchal;T. Kohda;Katsuaki Inoue;T. Oka;T. Suzuki;N. Yagi;H. Kitamura
为SPring-8高通量束线（BL 40 XU）研制了一台真空X射线螺旋波荡器。由于BL 40 XU没有配备单色仪以提供高光子通量，因此来自螺旋波荡器的轴上基波辐射在被水平和垂直反射镜聚焦后直接用于用户实验。在束线处可用的能量分辨率由波荡器光谱和前端物理孔径确定。与常规的SPring-8晶体单色器光束线相比，有效光子通量高出两个数量级。由于用户实验不要求特定的偏振状态，因此波荡器上没有定相机制。全新设计的磁铁结构，获得更好的磁场性能。测量的光谱带宽显示出与预期的一个很好的协议。
An in-vacuum X-ray helical undulator has been developed for a high flux beamline (BL40XU) of SPring-8. Since BL40XU is not equipped with a monochromator in order to provide high photon flux, on-axis fundamental radiation from the helical undulator is directly used for user experiments after being focused by horizontal and vertical mirrors. The energy resolution available at the beamline is determined by the undulator spectrum and the front end physical aperture. Compared to a conventional beamline of SPring-8 with a crystal monochromator, the available photon flux is higher by two orders. Since a specific polarization state is not requested from the user experiments, there is no phasing mechanics on the undulator. The magnet structure is newly designed to obtain better magnetic field performance. The measured spectral bandwidth shows a good agreement with the expected one.