The EMIL beamlines at BESSY II
The beamlines for the Energy Materials In-Situ Laboratory Berlin (EMIL) at BESSY-II are currently under commissioning. They consist of two canted undulators, providing a wide energy spectrum of 70 – 10.000 eV, three monochromators (two plane grating monochromators and one LN2-cooled double crystal monochromator) and ten mirror chambers for radiation dispersion and focusing into two separate pathways of 65 m length. Split-mirror chambers distribute the desired photon energy to one (or simultaneously to two) of five experimental endstations. The maximum lateral distance between all beamline elements is less than one meter. This narrow design, selectable monochromators and several beam crossings require advanced modification of all vacuum chambers to enable variable beam routes. Long pathways demand a very high mechanical and thermal stability as well as a reproducible motion of all optical elements. The chosen constant strut-length hexapod design for the mirror chambers provides a wide range of movement in six degrees of freedom.