Optical design study of the PEARL beamline at SLS

The PEARL beamline (Photo-Emission and Atomic Resolution Laboratory) uses a plane grating monochromator (PGM) concept. It operates in the −1 diffraction order ( | α | < | β | ) . It is based on a bending magnet covering an energy range between 100 and 2000 eV. Performance calculations for three different gratings were done (600, 1200 and 1800 l/mm). The maximum delivered flux of the three gratings for the proposed beamline layout is between 1010 and 1011 photons/s/0.1%BW. Furthermore a resolving power optimization was performed, as a result, the highest achieved resolving power at 1000 eV is around 10,000.