Published August 2015 | Version v1
Journal article

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

  • 1. Technische Universitaet Muenchen, Physik-Department, Garching (Germany)
  • 2. Max-Planck-Institut fuer Physik, Munich (Germany)
  • 3. Universidade de Coimbra, CIUC, Departamento de Fisica, Coimbra (Portugal)
  • 4. Laboratori Nazionali del Gran Sasso, INFN, Assergi (Italy)
  • 5. Walther-Meissner-Institut fuer Tieftemperaturforschung, Garching (Germany)
  • 6. Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany)
  • 7. Vienna University of Technology, Atominstitut, Wien (Austria)
  • 8. Institut fuer Hochenergiephysik der Oesterreichischen Akademie der Wissenschaften, Wien (Austria)
  • 9. University of Oxford, Department of Physics, Oxford (United Kingdom)
  • 10. University of Bern, Albert Einstein Center for Fundamental Physics, Bern (Switzerland)

Description

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 ∝0.60 keV and a resolution of 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 3GeV/c2. In this paper, we discuss the novel detector design and the surface-alpha event rejection in detail. (orig.)

Availability note (English)

Available from: http://dx.doi.org/10.1140/epjc/s10052-015-3572-9

Additional details

Publishing Information

Journal Title
European Physical Journal. C, Particles and Fields (Online)
Journal Volume
75
Journal Issue
8
Journal Page Range
p. 1-8
ISSN
1434-6052