Normal incidence monochromators for synchrotron radiation sources

Abstract

General considerations for the design of normal incidence monochromators for synchrotron radiation sources are described. The small divergence and the polarization of the incoming beam can be exploited in order to have a high proton flux and polarized light behind the exit slit. The size of the particle beam in the accelerator determines the wavelength resolution or the ratio between intensity and resolution. In particle one has to take into account in addition the distance from the source, the acceptance of the ootics and the aperture of the monochromator. The use of normal incidence monochromators is discussed in view of experiments requiring either high intensity, like the study of secondary processes (luminescence, photoemession, photofragmentation, …) or high wavelength resolution (spectroscopy on atoms and molecules).