Tender x-ray microfocus beamline employing a combined double crystal/multilayer grating monochromator.

A new x-ray beamline at the Physikalisch-Technische Bundesanstalt laboratory at BESSY II provides monochromatized radiation in the energy range from 1 to 10 keV, with a typical focus size of 20 μm. It is not only optimized for high-resolution x-ray spectrometry and microscopy but also enables scattering experiments and radiometric measurements. The innovative monochromator consists of a plane grating monochromator module equipped with multilayer-coated blazed gratings for x-ray energies up to 4 keV and an integrated double-crystal monochromator module equipped with silicon (111) crystals for x-ray energies ranging from 2.4 to 10 keV. The microfocus is produced by Kirkpatrick-Baez optics, achieving a minimal focus size of 5 × 7 μm2. Here, we present the design and performance parameters that were determined during the commissioning of the beamline which is in operation since mid-2024.