The XAFS fluorescence detector system based on 64 silicon drift detectors for the SESAME synchrotron light source

摘要

SESAME (Synchrotron-light for Experimental Science and Application in the Middle East) is a "third-generation" synchrotron light source. The Middle East's first major international research centre, established as cooperative venture by the scientists and governments of the region, is situated in Jordan. On the basis of the agreement signed between INFN and SESAME, our collaboration has designed and is building a Fluorescence Detector System based on 64 SDDs, each having a 9 mm(2) non-collimated sensitive area, realized with eight monolithic arrays for a total collimated sensitive area of 499 mm(2). The instrument will be used at the beamline dedicated to x-ray absorption spectroscopy in the energy range 3-30 keV with the capability of reaching a maximum counting rate of at least 3.2 Mcps. The energy resolution required for this application is below 150 eV FWHM @5.9 keV. We plan to have the system completely operative by July 2018. We report on the main building blocks of this system, dedicated to SESAME, and describe the experimental performances measured in the lab and on the XAFS beamline of ELETTRA Sincrotrone Trieste, Italy. In the very first tests the system was successfully operated up to 8 Mcounts/s. The energy resolution below 150 eV @5.9 keV was measured using a 1.6 mu s peaking time with the detector cooled to 10 degrees C.