Dark Matter Direct Detection: Exploring the MeV Mass Range

Astronomical measurements show that the universe is predominantly dark: 85% of matter in the universe is so-called dark matter. While the existence of dark matter is considered proven, its composition remains entirely unknown. We are attempting to solve this mystery with the CRESST experiment which aims at detecting potential interactions of dark matter particles. CRESST is an experiment optimized for the detection of light-dark matter particles; the key enabler is an extremely low energy threshold for the detection of particle interactions in the target crystals. Currently, the sensitivity of CRESST, and all other experiments of this type, is limited by the appearance of a so-far not fully understood background, denoted low-energy-excess (LEE). With this project (Dark Matter Direct Detection: Exploring the MeV Mass Range), we contribute to the efforts of CRESST to solve this LEE, by setting up a detector test facility at the HEPHY in Vienna and by analyzing prototype data. Based on new findings, CRESST foresees the construction of excess-free detectors whose dark matter data will be analyzed in the frame of this project. For this job, we will also (further) develop data analysis software and perform Monte Carlo simulations to precisely determine the backgrounds in the CRESST experiment. This project is part of the Collaborative Research Center Neutrinos and Dark Matter in Astro- and Particle Physics", funded by DFG (Germany) and FWF (Austria). It is embedded in the joint research group for the search for rare events (Rare Event Search) of the Atominstitut of TU Wien and the Institute for High Energy Physics in Vienna (HEPHY, Austrian Academy of Sciences). It is led by Florian Reindl (TU Wien).