Light-element sensitive in-air millibeam PIXE setup for fast measurement of atmospheric aerosol samples

Abstract

A sensitive in-air millibeam PIXE setup has recently been installed at the external beamline of the ATOMKI 2 MV Tandetron accelerator (Debrecen, Hungary) for high-throughput analysis of samples with short measurement time (100–300 s). The setup contains an X-ray detector cluster, 2 positioning lasers, a digital camera-microscope, an x–y precision stage, a Faraday cup and a measurement control and data acquisition system. By default, the detector cluster incorporates three 65 mm² SDD detectors with 12.5 micrometer Be window and one 30 mm² SDD with an ultra-thin Si₃N₄ window. In a 2 l min⁻¹ He flow, the system enables the simultaneous detection of X-rays from 0.35 keV to 26 keV, i.e. elements with Z > 6. The analytical characteristics are demonstrated further through analysis of reference materials. The effect of He saturation level on the calculated concentration of light elements is also shown. The new in-air PIXE system is suitable for the quantitative elemental characterization of both thin and thick samples with high sensitivity and good efficiency. The broad elemental range makes it particularly suitable for the analysis of atmospheric aerosol samples and archaeological, museum objects.