Multielement Si(Li) detector for the hard x-ray microprobe at ID22 (ESRF).

The hard x-ray microprobe beamline, ESRF-ID22, is primarily devoted to x-ray fluorescence spectroscopy. New requirements in terms of detection limits and acquisition rates fostered the installation and commissioning of a new Gresham multielement Si(Li) detector. It is based on a concentric and oriented array of 13 Si(Li) crystals viewing the same emission point. Beyond the energy resolution, linearity tests, and measurements of detection limits, the influence of the geometrical arrangement of the 13 elements has been investigated. In particular, the relationship between the scattering contribution to the fluorescence spectra and the angular position of individual Si(Li) crystals has been assessed. After optimization, the acquisition time can be reduced by a factor of 10 compared to what can be achieved with a single-element Si(Li) detector. [ABSTRACT FROM AUTHOR]