The RBS data furnace: Simulated annealing

Abstract A computer program was written which carries out an automatic analysis of Rutherford Backscattering (RBS) data with minimal human involvement. The inputs which are required are the system parameters (e.g. experimental geometry, energy calibration), and the elements present in the sample. Parameters such as the number of layers, layer thickness and layer composition, are determined automatically during the procedure. The global optimisation simulated annealing (SA) algorithm was used, due to its two main features: First, the solution is independent of the initial guess chosen, and therefore a human-input initial layer structure is not needed. Second, it tends asymptotically to the absolute global minimum rather than a local minimum as in conventional minimisation algorithms, and hence high quality solutions can be achieved.