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An innovative X-ray inspection technology, named XSpectra (R), has been developed with the aim to improve the current state of art in the field of real-time detection of contaminants in food products on production lines. The technology architecture is based on modules equipped with a 128 pixels CdTe array detector each read-out by full-custom Front-End ASICs. A full-custom Multi-Channel-Analyzer reconstructs the radiation spectrum, which is then processed by advanced Neural Network algorithms performing both image reconstruction and foreign bodies detection. The experimental characterization of XSpectra (R) has demonstrated the sensitivity of the fully operating system to photon energies down to about 10 keV at events rates up to several millions of photons per second. A line-width of 8.5 keV FWHM has been measured, at room temperature, on the 60 keV photo-peak of a synchrotron radiation in low-rate conditions. A spectral non-linearity error within +/- 0.5% has been obtained within the energy range 25 keV -100 keV. The effective capability of XSpectra (R) to detect currently undetectable low-density contaminants inside real food products has also been proved.

Subaquatic mass movements are common in marine and lacustrine environments, but due to their barely pre- dictable nature, direct observations of these processes are limited so that knowledge is only indirectly obtained by investigating the resulting mass-transport deposits (MTDs). Most research focuses on the most common fron- tally emergent slides, fast-moving events able to generate turbidity currents and tsunamis. Geohazards of fron- tally confined slides and mechanisms behind their typical fold-and-thrust deformation structures are however still poorly understood. We investigate frontally confined MTDs in Lake Lucerne (Switzerland) by integrating bathymetric and high-res- olution seismic data with geotechnical information derived from in situ Cone Penetrometer Tests and short core analysis. Investigated MTDs consist of three units: i) a mass-slide deposit, located at the base of the slope consisting of a coherent slope sequence, ii) a fold-and-thrust system developed in basin sediments, and iii) an overrunning mass flow deposit, consisting of remolded slope sediments. The deformed and thrusted basin sed- iments show higher undrained shear strength compared to the undisturbed basin sequence. We propose that this strengthening is caused by lateral compression leading to fluid expulsion in the high-plasticity basin sedi- ments by the bulldozing sliding mass. Relative kinematic indicators document that the fold-and-thrust deforma- tion structures occur rapidly. Thus, they should be considered in tsunami hazard analysis. Furthermore, our data highlight that the slope angle of the gliding surface and basin topography are key controlling factors for slope sta- bility and propagation of basin-plain deformations, respectively. Our integrated study supports and refines prop- agation models proposed in marine environments, revealing the potential of investigating smaller-scale easier- to-access MTDs in lakes.

Low-energy X-ray fluorescence (LEXRF) is an essential tool for bio-related research of organic samples, whose composition is dominated by light elements. Working at energies below 2 keV and being able to detect fluorescence photons of lightweight elements such as carbon (277 eV) is still a challenge, since it requires in-vacuum operations to avoid in-air photon absorption. Moreover, the detectors must have a thin entrance window and collect photons at an angle of incidence near 90 degrees to minimize the absorption by the protective coating. Considering the low fluorescence yield of light elements, it is important to cover a substantial part of the solid angle detecting ideally all emitted X-ray fluorescence (XRF) photons. Furthermore, the energy resolution of the detection system should be close to the Fano limit in order to discriminate elements whose XRF emission lines are often very close within the energy spectra. To ensure all these features, a system consisting of four monolithic multi-element silicon drift detectors was developed. The use of four separate detector units allows optimizing the incidence angle on all the sensor elements. The multi-element approach in turn provides a lower leakage current on each anode, which, in combination with ultra-low noise preamplifiers, is necessary to achieve an energy resolution close to the Fano limit. The potential of the new detection system and its applicability for typical LEXRF applications has been proved on the Elettra TwinMic beamline.