Beta/gamma and alpha backgrounds in CRESST-II Phase 2
Abstract
The experiment CRESST-II aims at the detection of dark matter with scintillating CaWO crystals operated as cryogenic detectors. Recent results on spin-independent WIMP-nucleon scattering from the CRESST-II Phase 2 allowed to probe a new region of parameter space for WIMP masses below 3 GeV/c. This sensitivity was achieved after background levels were reduced significantly. We present extensive background studies of a CaWO crystal, called TUM40, grown at the Technische Universit\"at M\"unchen. The average beta/gamma rate of 3.51/[kg keV day] (1-40 keV) and the total intrinsic alpha activity from natural decay chains of mBq/kg are the lowest reported for CaWO detectors. Contributions from cosmogenic activation, surface-alpha decays, external radiation and intrinsic alpha/beta emitters are investigated in detail. A Monte-Carlo based background decomposition allows to identify the origin of the majority of beta/gamma events in the energy region relevant for dark matter search.
Keywords
Cite
@article{arxiv.1410.4188,
title = {Beta/gamma and alpha backgrounds in CRESST-II Phase 2},
author = {R. Strauss and G. Angloher and A. Bento and C. Bucci and L. Canonica and A. Erb and F. v. Feilitzsch and N. Ferreiro Iachellini and P. Gorla and A. Gütlein and D. Hauff and J. Jochum and M. Kiefer and H. Kluck and H. Kraus and J. -C. Lanfranchi and J. Loebell and A. Münster and F. Petricca and W. Potzel and F. Pröbst and F. Reindl and S. Roth and K. Rottler and C. Sailer and K. Schäffner and J. Schieck and S. Scholl and S. Schönert and W. Seidel and M. v. Sivers and L. Stodolsky and C. Strandhagen and A. Tanzke and M. Uffinger and A. Ulrich and I. Usherov and S. Wawoczny and M. Willers and M. Wüstrich and A. Zöller},
journal= {arXiv preprint arXiv:1410.4188},
year = {2016}
}
Comments
17 pages, 7 figures, 3 tables