The Debrecen scanning proton microprobe facility and its applications to geological samples

The recently installed scanning proton microprobe of the Institute of Nuclear Research (ATOMKI) in Debrecen is supplied with proton beam from a home-made 5 MV single ended Van de Graaff accelerator, while focusing and scanning the beam is achieved by the commercially available system from Oxford Microbeams Ltd. including quadrupole doublet focusing lenses, slits, scanning coils and a PC-based data acquisition package. Its first PIXE application was made in micromineralogy, in the study of spherules. Spherules in different geological and geographical situations may have various extraterrestrial origin, Several of these objects uncovered in the western part of Hungary have been analysed. Cosmic origin can be supposed for the majority of the findings.