Microfocus

A second focusing bendable KB mirror system at 72.8 m downstream from the source can be used for further demagnification of the secondary source. This way the beamsize at the crystallography experiment can be freely adjusted between 4 × 9 µm² and 300 × 300 µm² FWHM (v × h) with 10¹³ ph/s at 12 keV (see Figure 1). Smaller beam sizes down to 1 × 1 µm² with more than 2 × 10¹¹ ph/s in the focus can be realized by slitting down the secondary source at the cost of flux as illustrated in Figure 2.

Figure 1: Microfocus with slits at secondary source fully open. Horizontal beamsize at sample position: 9 µm (FWHM). Data were collected at a photon energy of 8 keV.

Figure 2: Microfocus with slits at secondary source partially closed. Horizontal beamsize at sample position: 4 µm (FWHM).