Low-Temperature Scintillation Properties of CaWO4 Crystals for Rare-Event Searches

M. v. Sivers; M. Clark; P. C. F. Di Stefano; A. Erb; A. Gütlein; J. -C. Lanfranchi; A. Münster; P. Nadeau; M. Piquemal; W. Potzel; S. Roth; K. Schreiner; R. Strauss; S. Wawoczny; M. Willers; A. Zöller

arXiv · 1510.05787

Low-Temperature Scintillation Properties of CaWO4 Crystals for Rare-Event Searches

M. v. Sivers·M. Clark·P. C. F. Di Stefano·A. Erb·A. Gütlein·J. -C. Lanfranchi·A. Münster·P. Nadeau·M. Piquemal·W. Potzel·S. Roth·K. Schreiner·R. Strauss·S. Wawoczny·M. Willers·A. Zöller

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Abstract

In prospect of its application in cryogenic rare-event searches, we have investigated the low-temperature scintillation properties of CaWO4 crystals down to 3.4 K under α and γ excitation. Concerning the scintillation decay times, we observe a long component in the ms range which significantly contributes to the light yield below 40K. For the first time we have measured the temperature dependence of the α/γ- ratio of the light yield. This parameter which can be used to discriminate α and γ events in scintillating bolometers is found to be about 8-15% smaller at low temperatures compared to room temperature.

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M. v. Sivers, M. Clark, P. C. F. Di Stefano, A. Erb, A. Gütlein, J. -C. Lanfranchi, A. Münster, P. Nadeau, M. Piquemal, W. Potzel, S. Roth, K. Schreiner, R. Strauss, S. Wawoczny, M. Willers, A. Zöller. 2015-10-20. Low-Temperature Scintillation Properties of CaWO4 Crystals for Rare-Event Searches. https://arxiv.org/abs/1510.05787

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