The light source is the middle-point (4) between the undulator two sections (1) and (2) with phase modulator electormagnet (3). At 10 m from the source middle position, the pinhole (5) sets the beamline angular acceptance and stops unwanted radiation from the undulator. The toroidal mirror (6) demagnifies the source by a factor of 8 in the horizontal plane and 5.3 in the vertical.
The entrance slits are located at the horizontal (7) and vertical (8) foci of the toroidal mirror. The slit (7) becomes the virtual source for all of the following mirrors in the horizontal plane. The light is then dispersed by the monochromator (9), which also determines a further vertical demagnification by a factor 1.7. After the exit-slit (10), a retractable plane mirror (11) allows switching operation between the two branches of the beamline. The refocusing mirrors are two bendable elliptical cylinder mirrors arranged in a Kirkpatrick-Baez geometry. They are located in dedicated vacuum chambers (12). On beamline first branch, the demagnification introduced by these elements is 11.5 in the horizontal direction and 5 in the vertical direction. For the second branch, the demagnefication factors are 13.9 and 7.6, for the horizontal and the vertical direction respectively.
Physical layout of the beamline.
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