The Elio portable XRF Analyzer (PXRF) is composed of a large area Silicon Drift Detector: 25mm2 XRF Detector, 130 eV at MnKα with 10 kcps input photon rate (high resolution mode), 170 eV at MnKα with 200 kcps input photon rate (fast mode). It has a fast (USB 2.0) 8k channels MCA with high resolution and high count-rate capability. Its excitation source is a transmission X-Ray generator, 5-200 μA, 10-40 kV, Rh anode with 1mm collimator. It has two pointing lasers (axial and focal), a microscope camera permitting on field adjustments on analysis. A mounting tripod (height 43-188cm) completes the set-up and allows for an easy movement and positioning in front of the object at a distance of about 1 cm. Definite security procedures must be followed: only trained users can work with the instrument, they must stay behind the probe head at a distance ≥ 2.7m. The object to be investigated (and thus the direction of the X-ray beam) must be positioned in front of a concrete wall of a thickness ≥ 5cm.
The portable X-ray fluorescence allows for a determination of the elemental composition (atomic number, Z>12) of materials and is of great interest for heritage science applications particularly in the examination of inorganic materials of all types of paintings, manuscripts, monuments and metals etc. It is highly effective for a first hypothesis towards artist pigments identification, specifically inorganic constituents, highlighting pentimenti, retouchings and over-paintings etc.