First results of the soft X-ray microfocus beamline U41-PGM

We present the first experimental data obtained from the new microfocus bea mline U41-PGM recently put into operation. The optical layout of the beamli ne has been designed to conserve the high spectral brillance of the undulat or source. The beamline consists of a collimated plane grating monochromato r (PGM) and a subsequent refocusing stage. A toroidal mirror is used for re focusing onto the sample surface. With the 600 l/mm. grating an absolute ph oton flux between 10(12) and 10(13) photons per second has been recorded ov er the whole energy range. Although the monochromator is not designed to de liver highest energy resolution, a resolving power of up to 6000 at the nit rogen K-edge has been obtained recently. The fixfocus. constant c(ff) is va riable in a wide range. According to the experimental requirements it can b e set to select either high photon flux or energy resolution. (C) 2001 Else vier Science B.V. All rights reserved.