Research and Development of X-Ray Spectroscopy Based on Polycapillary Optics at Laboratori Nazionali di Frascati

In the last years, at the Laboratori Nazionali di Frascati the X-ray optics group has developed a series of prototypes based on polycapillary optics that allow to perform a full X spectroscopy analysis. This paper presents preliminary results for three different prototypes: the first allows transmission X-imaging with a resolution less than 6 μm; the second one allows 2D elemental mapping with a resolution less than 100×100×μm².

The identification of ice core insoluble mineral aerosol source areas is an important tool for the understanding of present day and past pathways of atmospheric transport toward the poles and the paleoclimatic information. To achieve this result it is very helpful to determine the geochemical composition of atmospheric dust particles deposited over the ice sheets and archived in ice core samples and to compare it with the composition of potential source areas sediments. The main experimental challenge is the very low concentration of mineral materials trapped in the snow, especially for Antarctic firn and ice samples, typically around 10-20 ppb (∼5000 particles/cm³). A complete studies of elemental concentrations in the ppb range (such as insoluble dust in deep ice core) require ultimate cleaning procedures to collect, prepare and perform nondestructive experiments, that require a very bright X-ray sources, such as synchrotron radiation, combined with a total external reflection regime. Based on a polycapillary semi-lens, here is reported preliminary results of a complete portable prototype that allows to obtain elemental measurements in total external reflection regime.

At Laboratori Nazionali di Frascati is currently under development and design of a single prototype that allows users to make all the techniques of fluorescence spectroscopy and X-imaging.