Eur. Phys. J. C (2014) 74: 3184
https://doi.org/10.1140/epjc/s10052-014-3184-9

Letter

Results on low mass WIMPs using an upgraded CRESST-II detector

¹ Max-Planck-Institut für Physik, 80805, Munich, Germany
² Departamento de Fisica, Universidade de Coimbra, 3004 516, Coimbra, Portugal
³ INFN, Laboratori Nazionali del Gran Sasso, 67010, Assergi, Italy
⁴ Physik-Department, Technische Universität München, 85747, Garching, Germany
⁵ Walther-Meißner-Institut für Tieftemperaturforschung, 85748, Garching, Germany
⁶ Institut für Hochenergiephysik der Österreichischen Akademie der Wissenschaften, 1050, Wien, Austria
⁷ Atominstitut, Vienna University of Technology, 1020, Wien, Austria
⁸ Eberhard-Karls-Universität Tübingen, 72076, Tübingen, Germany
⁹ Department of Physics, University of Oxford, Oxford, OX1 3RH, UK

^* e-mail: freindl@mpp.mpg.de

Received: 14 July 2014
Accepted: 16 November 2014
Published online: 9 December 2014

Abstract

The CRESST-II cryogenic dark matter search aims for the detection of WIMPs via elastic scattering off nuclei in CaWO$$_4$$ crystals. We present results from a low-threshold analysis of a single upgraded detector module. This module efficiently vetoes low energy backgrounds induced by $$\alpha $$-decays on inner surfaces of the detector. With an exposure of 29.35 kg live days collected in 2013 we set a limit on spin-independent WIMP-nucleon scattering which probes a new region of parameter space for WIMP masses below 3 GeV/c$$^2$$, previously not covered in direct detection searches. A possible excess over background discussed for the previous CRESST-II phase 1 (from 2009 to 2011) is not confirmed.