The new in-air micro-PIXE setup in Atomki, Debrecen

Full text: In this work we present a new in-air micro-PIXE measurement setup installed at the Laboratory of lon Beam Applications of Atomki, Debrecen, Hungary. The new external measurement system was set up on the nuclear microprobe beamline. An external beam add-on system by Oxford Microbeams was mounted on the already existing microprobe vacuum chamber. The samples are positioned by using a digital microscope, two alignment lasers and a precision XYZ stage. The measurement system is equipped with two X-ray detectors for PIXE analysis, a surface barrier detector for RBS and a HP-Ge detector for γy-ray detection. The arrangement permits the combination of these techniques either simultaneously or separately, too. The beam current is measured with a beam chopper placed in the vacuum chamber. Exit windows with different thickness and of different materials can be used according to the actual demands. At the moment kapton foils of 8 μm thicknesses and silicon nitride (Si₃N₄) films with 100 nm, 200 nm and 500 nm thicknesses are at our disposal. The thickness, density and composition of the window materials were measured by profilometry and by RBS, STIM and PIXE in order to check whether the parameters provided by the producers were real. The capability of the new in-air micro-PIXE setup was demonstrated on standard reference materials and on geological (a stalactite) and archaeological samples. (author)