Description
The CRESST experiment, located at the Laboratori Nazionali del Gran Sasso (LNGS), is a leading dark matter direct detection experiment. It employs cryogenic calorimeters operated at millikelvin temperatures and instrumented with Transition Edge Sensors (TES), achieving extremely low energy thresholds and high sensitivity to sub-GeV dark matter particles. However, the experiment's sensitivity is currently limited by an unexplained increase in background events below ~200 eV, known as the Low-Energy Excess (LEE).
Prompted by observations presented at previous EXCESS Workshops, we show a dedicated above-ground R&D study aimed at investigating possible origins of the LEE. In particular, we study the effect of thermal cycles from room temperature to 4 K on the LEE decay rate. This study provides new insights into the nature and mechanisms of the LEE.