Imaging and spectroscopic performances of the detector assemblies for the lunar electromagnetic monitor in x-rays

The Lunar Electromagnetic Monitor in X-rays (LEM-X) is an Italian proposal for a Moon-based all-sky X-ray observatory, for the detection of transients and the long-term monitoring of sources in the 2−50 keV band, developed within the Earth Moon Mars project of the Italian National Recovery and Resilience Plan. Featuring a modular design, LEM-X is based on compact and lightweight coded-aperture cameras, each with a 2 sr field of view. The detector plane of each camera is built around four alumina-based Detector Assemblies (DAs), each one featuring a large-area (∼7×7 cm2) Silicon Drift Detector (SDD), readout by CMOS analog Application Specific Integrated Circuits (AFE ASICs) named NOVA and specifically developed for this project. Four complete DAs, i.e. the full detector plane of one LEM-X camera, were developed and assembled. We will present the results of the performance tests demonstrating both the spectral and imaging capabilities of the devices.