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The Cryogenic Rare Event Search with Superconducting Thermometers (CRESST) is a collaboration of European experimental particle physics groups involved in the construction of cryogenic detectors for direct dark matter searches. The participating institutes are the Max Planck Institute for Physics (Munich), Technische Universität München, Universität Tübingen, University of Oxford (Great Britain) and the Istituto Nazionale di Fisica Nucleare (INFN, Italy).
The CRESST collaboration currently runs an array of cryogenic detectors in the underground laboratory of the Gran Sasso National Laboratory. The modular detectors used by CRESST facilitate discrimination of background radiation events by the simultaneous measurement of phonon and photon signals from scintillating calcium tungstate crystals. By cooling the detectors to temperatures of a few millikelvin, the excellent discrimination and energy resolution of the detectors allows identification of rare particle events.
CRESST-I took data in 2000 using sapphire detectors with tungsten thermometers. CRESST-II uses CaWO4 crystal scintillating calorimeters. It was prototyped in 2004 and had a 47.9 kg-day commissioning run in 2007 and operated 2009 to 2011. Phase 2 has a new CaWO4 crystal with better radiopurity, improved detectors, and significantly reduced background. It began July 2013, to explore excess signals in the prior run.
CRESST-I first detected the alpha decay of tungsten. CRESST-II phase 1 full results were published in 2012. New phase 2 results have been presented on July 2014 with a limit on spin-independent WIMP-nucleon scattering for WIMP masses below 3 GeV/c2.
In 2015 the CRESST detectors were upgraded by a sensitivity factor of 100 allowing dark matter particles with a mass around that of a proton to be detected.
The EURECA experiment is a planned successor to CRESST, ultimately aiming to run an array of detectors with a total mass of around 1 tonne.