Abstract
The cryogenic dark matter experiment CRESST-II aims at the direct detection of WIMPs via elastic scattering off nuclei in scintillating CaWO(Formula presented.)4 crystals. We present a new, highly improved, detector design installed in the current run of CRESST-II Phase 2 with an efficient active rejection of surface-alpha backgrounds. Using CaWO(Formula presented.)4 sticks instead of metal clamps to hold the target crystal, a detector housing with fully-scintillating inner surface could be realized. The presented detector (TUM40) provides an excellent threshold of (Formula presented.)∼0.60 keV and a resolution of (Formula presented.)σ≈0.090 keV (at 2.60 keV). With significantly reduced background levels, TUM40 sets stringent limits on the spin-independent WIMP-nucleon scattering cross section and probes a new region of parameter space for WIMP masses below 3 GeV/c(Formula presented.)2. In this paper, we discuss the novel detector design and the surface-alpha event rejection in detail.
Originalsprache | Englisch |
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Aufsatznummer | 352 |
Fachzeitschrift | European Physical Journal C |
Jahrgang | 75 |
Ausgabenummer | 8 |
DOIs | |
Publikationsstatus | Veröffentlicht - 1 Aug. 2015 |