Search

The next generation direct dark matter experiment CRESST-III has a high potential to significantly increase the sensitivity to low-mass WIMPs (mx ≲10 GeV/c2). We present the new CRESST detector module: it consists of a 24 g CaWO4 crystal operated as a phonon detector and a 20x20 mm^2 silicon-on-sapphire light detector. The phonon energy threshold is lowered to ~100 eV and a light detector resolution of typically 5 eV is achieved. A fully-scintillating inner detector housing is realised which efficiently rejects events from surface alpha decays. The CaWO4 sticks holding the target crystal are also operated as calorimeters to discriminate all possible artefacts related to the support structure. A projection for the sensitivity to spin-independent WIMP-nucleon scattering is given for the first phase of CRESSTIII which will start beginning of 2016.

The CRESST-II experiment is searching for dark matter particles via their elastic scattering off nuclei in a target material. The CRESST target consists of scintillating CaW04 crystals which are operated as cryogenic calorimeters at millikelvin temperatures and read out by transition edge sensors. Each interaction in the CaW04 target crystal produces a phonon signal and also a light signal that is measured by a secondary cryogenic calorimeter. The low energy thresholds of these detectors, combined with the presence of light nuclei in the target material, allow to probe the low-mass region of the parameter space for spin-independent dark matter-nucleon scattering with high sensitivity. In this contribution results from a blind analysis of one detector module operated in the latest measurement campaign are presented. An unprecedented sensitivity for the light dark matter has been obtained with 52kg live days and a threshold of 307eV for nuclear recoils, extending the reach of direct dark matter searches to the sub-GeV/c2 region.