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Abstract

In the present doctoral thesis, I focused on the analysis of cultural heritage objects. The artefacts have a historical value and need to be handled with extreme caution. The analysis has then relied on non-destructive methods, such as the method of proton-induced X-ray emission (PIXE) and the method of proton-induced gamma ray emission (PIGE). With PIXE, we cannot detect light elements, so the method of proton-induced gamma rays emission was used. With these two methods, we analyzed different samples: glass, precious stones, ancient coins, brass, examples of bronze firearms, color pigments. We developed a system for elemental mapping of the samples. The new mapping system complements and upgrades the PIXE method, because with this system we can analyze samples more clearly and in more detail. The system was constructed at the external (in air) beamline of the Microanalytical Centre at the Jožef Stefan Institute. With the method we developed, we can determine the elemental maps, thus showing the spatial distribution of elements in the sample. The sample is prepared and attached to the control table. With precision motors we move the sample in the x-y direction with an accuracy of 0.01 mm. With respect to the size of the proton beam, we select the step between scanning points, in our case we chose a 1 mm step. During the measurements, the data is automatically saved. After the measurements, the data are processed, we calculate the concentrations of the elements and draw elemental maps. The system was first tested on a sample of archaeological bronze. After the system was fully understood, we carried out measurements on a selection of samples (historical coins, metal fragments, manuscripts in the book, etc.). With these data we can recognize a variety of processes concerning manufacture of the objects, particularly the structure and methods of manufacturing thin metal layers, such as in tinning-silvering and by amalgamation. With our mapping system we have achieved that we can extract more data from the sample at the same time, and thus supplemented the PIXE method.