Variable Rowland radius laboratory EXAFS system

We report here on a new EXAFS laboratory facility. It features a variable Rowland radius with a source to bent crystal distance that can vary from 250 to 750 mm. It has a sample carrying table which is mechanically detached from the monochromator and can carry more than 50 lb with no effect on the monochromator. The system is completely computer controlled in such a way that the operator can control every part of the system separately as well as perform complete automatic runs. The data-analysis programs had been divided into a general package which performs the bookkeeping of files experimental parameters and program parameters and a specific package for the analysis of the EXAFS data. The monochromator is shown to have almost theoretical resolution. We present experimental results of EXAFS on copper. The Fourier transform of these spectra agree very well with the Fourier transform of EXAFS spectra measured on a synchrotron. It is shown that the resolution of 4.5 eV of these data does not present a limitation on the quality of the data. The signal-to-noise ratio is, on the other hand, quite critical.