Instrumental aspects of synchrotron XUV spectroscopy

Electron synchrotrons are becoming increasingly important as sources of extreme uv radiation for physical experiments. The NBS 180-MeV machine has been utilized for gas absorption studies over a four-year period, during which a 3-m grazing incidence spectrograph and monochromator have been designed, constructed and put into operation. The instruments are extremely stable to vibration and temperature variation, and are operating with a slit limited resolution of the order of 0.06 A. The design principles and features of these instruments are described, and a highly successful prealignment procedure for grazing incidence spectrometers is outlined. The effect of the unusual characteristics of this light source on the illumination and performance of the spectroscopic instruments is discussed.