An XRF method for the determination of the efficiency of Si(Li) detectors in an extended-source geometry by using thick specimens

An XRF method for the determination of the relative efficiency of Si(Li) detectors in an annular-source geometry using 109Cd is presented. Thick specimens of pure metals and stable compounds are used and the usual computational problems associated with such efficiency determination are circumvented by employing a Monte Carlo technique. The results obtained are compared with the theoretical calculation of a model based efficiency. The deviations at lower and higher energies in the energy range between 4.5 and 17.5 keV are observed and explained. (orig.)