SOFTWARE FOR MODELING POSITRON-BEAM DEPTH-PROFILING DATA

The fitting program VEPFIT has been extended with applications running under the Microsoft Windows environment facilitating the input and ou tput of the VEPFIT fitting module. We have exploited the Microsoft-Win dows(R) graphical users interface by making use of dialog windows, scr ollbars, command buttons etc. The user communicates with the program s imply by clicking and dragging with the mouse pointing device. Keyboar d actions are limited to a minimum. Upon changing one or more input pa rameters the results of the modeling of the S-parameter and Ps-fractio n versus positron implantation energy are updated and displayed. This action can be considered as the first step in the fitting procedure up on which the user can decide to further adapt the input parameters or to forward these parameters as initial values to the fitting routine. The modeling step has proven to be helpful for designing positron beam experiments.