A detector module with highly efficient surface-alpha event rejection operated in CRESST-II Phase 2

作者：Strauss R^*; Angloher G; Bento A; Bucci C; Canonica L; Erb A; von Feilitzsch F; Ferreiro N; Gorla P; Guetlein A; Hauff D; Jochum J; Kiefer M; Kluck H; Kraus H; Lanfranchi J C; Loebell J; Muenster A; Petricca F; Potzel W; Proebst F; Reindl F; Roth S; Rottler K; Sailer C; Schaeffner K; Schieck J; Scholl S; Schoenert S; Seidel W; von Sivers M; Stanger M; Stodolsky L; Strandhagen C; Tanzke A; Uffinger M; Ulrich A; Usherov I

来源：European Physical Journal C, 2015, 75(8): 352.

DOI：10.1140/epjc/s10052-015-3572-9

The cryogenic dark matter experiment CRESSTII aims at the direct detection of WIMPs via elastic scattering off nuclei in scintillating CaWO4 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 CaWO4 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 similar to 0.60 keV and a resolution of sigma approximate to 0.090 keV (at 2.60 keV). With significantly reduced background levels, TUM40 sets stringent limits on the spin-independent WIMPnucleon scattering cross section and probes a new region of parameter space for WIMP masses below 3 GeV/c(2). In this paper, we discuss the novel detector design and the surface-alpha event rejection in detail.

• 出版日期2015-7-31