The first use of transmission gratings for measurements of optical constants in the soft X-ray range

Abstract

In this paper we describe the results of an experiment at SSRL which was designed to provide data for the computation of the optical constants of gold. Basically, the experiment recorded the intensity spectra of several specially manufactured gold transmission gratings prepared at IBM for this purpose, and the spectra were analyzed and the intensity ratios used to compute the optical constants. Additional measures of the gratings' imperfections (done at IBM) and of the observed spectral imperfections of the 4° soft X-ray monochromator at SSRL were also used to correct the measured spectra in suitable ways, and all the apparent systematic and random errors were incorporated into the error limits given with the computed constants. This paper summarizes the experimental processes, their shortcomings and results, and discusses those areas where significant improvements in the systematic error are clearly possible.