Dark Matter detection with the COSINUS experiment

Using a NaI target is essential to test the long-standing DAMA/LIBRA claim of the detection of a Dark Matter (DM) signal in a model -independent way. COSINUS is developing the first cryogenic scintillating calorime-ter based on a NaI absorber. This technique provides an event-by-event particle identification strategy based on a dual-channel readout (heat and light). An ex-cellent energy resolution and a low threshold are essential for a direct detection DM experiment. In this regard, Transition Edge Sensors (TESs) are an established technology that has already proven its potential in other leading cryogenic DM experiments (like CRESST-III). However, the hygroscopicity of NaI prevents the deposition of the TES sensor directly onto its surface, which would guarantee opti-mal thermal coupling. For this reason, COSINUS adopted an alternative design for the heat channel readout, called remoTES, which is currently in the R & D phase and has already shown promising results (in terms of energy threshold and resolution) when tested on various absorbers (Si, TeO2).