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arXiv · 1506.04305

Studies of scintillation properties of CaMoO4 at millikelvin temperatures

X. Zhang·J. Lin·V. B. Mikhailik·H. Kraus
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Abstract

Application of CaMoO4 as a scintillation target in cryogenic rare event searches relies on the understanding of scintillation properties of the material at the temperatures at which these detectors operate. We devised and implemented a detection module with a low-temperature photomultiplier from Hamamatsu (model R8520-06) powered by a Cockcroft-Walton generator. The detector module containing the CaMoO4 crystal was placed in a 3He/4He dilution refrigerator and used to measure scintillation characteristics of CaMoO4 in the millikelvin temperature range. At the lowest temperature achieved, the energy resolution of CaMoO4 for 122 keV from a 57Co source is found to be 30% (FWHM), and the fast and slow decay constants are 40.6+-0.8 us and 3410+-50 us, respectively. The temperature variation of the CaMoO4 decay kinetics is discussed in terms of a three-level model of the emission center

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X. Zhang, J. Lin, V. B. Mikhailik, H. Kraus. 2015-06-13. Studies of scintillation properties of CaMoO4 at millikelvin temperatures. https://doi.org/10.1063/1.4922875

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