N-BEAM INTERACTIONS EXAMINED WITH THE HELP OF THE COMPUTER-PROGRAMS PSIINT AND PSILAM

Two computer programs - one for calculation and graphical representation of the azimuthal angle ψ of all possible multiple reflections versus the wavelength λ (PSILAM) and one for the simulation of the Umweganregung-intensity variation during rotation of the crystal about the scattering vector of a 'forbidden' or very weak reflection (PSIINT) - have been developed on the basis of the program UMWEG with emphasis on suitability for inexpensive hardware. Examples of the excellent agreement between measurements and calculations and of the necessity of the combined application of both programs are given.