Beamline Optics

lN2 cooled fixed-exit
Si(111) monochromator
Dynamically bendable mirror
Source distance 28.58 m 29.43 m
Focusing Sagittal - horizontal Meridional - vertical
The first monochromator crystal is liquid nitrogen cooled. The second crystal is not cooled. The first crystal is moved along the beam as a function of energy whereas the second crystal is only rotated, i.e., it is a fixed exit monochromator. With the bending mechanism for the second crystal a spot size of down to 20 µm FWHM at the sample position can be reached in the horizontal direction.

The fused silica mirror has three stripes with different coatings, namely Rhodium, Platinum and no coating. It is used for higher harmonic rejection and via a bending mechanism a spot size down to 5 µm at the sample position can be reached in the vertical direction.

The focusing in both directions is variable and therefore focusing in the detector plane essentially on a single detector pixel or not focusing at all is feasible as well.