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arXiv · 0809.1829

Commissioning Run of the CRESST-II Dark Matter Search

G. Angloher·M. Bauer·I. Bavykina·A. Bento·A. Brown·C. Bucci·C. Ciemniak·C. Coppi·G. Deuter·F. von Feilitzsch·D. Hauff·S. Henry·P. Huff·J. Imber·S. Ingleby·C. Isaila·J. Jochum·M. Kiefer·M. Kimmerle·H. Kraus·J. -C. Lanfranchi·R. F. Lang·B. Majorovits·M. Malek·R. McGowan·V. B. Mikhailik·E. Pantic·F. Petricca·S. Pfister·W. Potzel·F. Proebst·W. Rau·S. Roth·K. Rottler·C. Sailer·K. Schaeffner·J. Schmaler·S. Scholl·W. Seidel·L. Stodolsky·A. J. B. Tolhurst·I. Usherov·W. Westphal
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Abstract

The CRESST cryogenic direct dark matter search at Gran Sasso, searching for WIMPs via nuclear recoil, has been upgraded to CRESST-II by several changes and improvements.We present the results of a commissioning run carried out in 2007. The basic element of CRESST-II is a detector module consisting of a large (~ 300 g) CaWO_4 crystal and a very sensitive smaller (~ 2 g) light detector to detect the scintillation light from the CaWO_4.Information from light-quenching factor studies allows the definition of a region of the energy-light yield plane which corresponds to tungsten recoils. A neutron test is reported which supports the principle of using the light yield to identify the recoiling nucleus. Data obtained with two detector modules for a total exposure of 48 kg-days are presented. Judging by the rate of events in the "all nuclear recoils" acceptance region the apparatus shows a factor ~ten improvement with respect to previous results, which we attribute principally to the presence of the neutron shield. In the "tungsten recoils" acceptance region three events are found, corresponding to a rate of 0.063 per kg-day. Standard assumptions on the dark matter flux, coherent or spin independent interactions,then yield a limit for WIMP-nucleon scattering of 4.8 \times 10^{-7}pb, at M{WIMP} ~50 GeV.

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G. Angloher, M. Bauer, I. Bavykina, A. Bento, A. Brown, C. Bucci, C. Ciemniak, C. Coppi, G. Deuter, F. von Feilitzsch, D. Hauff, S. Henry, P. Huff, J. Imber, S. Ingleby, C. Isaila, J. Jochum, M. Kiefer, M. Kimmerle, H. Kraus, J. -C. Lanfranchi, R. F. Lang, B. Majorovits, M. Malek, R. McGowan, V. B. Mikhailik, E. Pantic, F. Petricca, S. Pfister, W. Potzel, F. Proebst, W. Rau, S. Roth, K. Rottler, C. Sailer, K. Schaeffner, J. Schmaler, S. Scholl, W. Seidel, L. Stodolsky, A. J. B. Tolhurst, I. Usherov, W. Westphal. 2009-02-16. Commissioning Run of the CRESST-II Dark Matter Search. https://doi.org/10.1016/j.astropartphys.2009.02.007

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