Performances of a large mass ZnSe bolometer to search for rare events
Performances of a large mass ZnSe bolometer to search for rare events
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DOI：
10.1088/1748-0221/8/05/p05021
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发表时间：
2013-05-01
影响因子：
1.3
通讯作者：
Vignati, M.
中科院分区：
文献类型：
--
作者：
Beeman, J. W.;Bellini, F.;Vignati, M.
闪烁的锌硒测辐射热计是路西法实验的基线选择，其目的是观察Se-82的无中微子双β衰变。热和闪烁信号的独立读出允许识别和拒绝阿尔法粒子相互作用，阿尔法粒子相互作用是辐射热学探测器的主要背景来源。本文报道了在路西法研发中心工作的锌硒晶体的性能。我们测量了闪烁产额、能量分辨率和能区本底，在9.4kg.天的曝光量下，预计0nu DBD衰变信号出现在Se-82的能区。利用一种新开发的分析算法，我们改进了对α事件的拒绝，并估计了热和光信号组合所获得的能量分辨率的增加。我们第一次测量了核反冲发出的光，发现它与零相容。我们的结论是，在WIMPS能区区分核反冲和β/伽马相互作用是可能的，但需要低噪声的光探测器。
Scintillating bolometers of ZnSe are the baseline choice of the LUCIFER experiment, whose aim is to observe the neutrinoless double beta decay of Se-82. The independent read-out of the heat and scintillation signals allows to identify and reject alpha particle interactions, the dominant background source for bolometric detectors. In this paper we report the performances of a ZnSe crystal operated within the LUCIFER R&D. We measured the scintillation yield, the energy resolution and the background in the energy region where the signal from 0 nu DBD decay of Se-82 is expected with an exposure of 9.4kg.days. With a newly developed analysis algorithm we improved the rejection of alpha events, and we estimated the increase in energy resolution obtained by the combination of the heat and light signals. For the first time we measured the light emitted by nuclear recoils, and found it to be compatible with zero. We conclude that the discrimination of nuclear recoils from beta/gamma interactions in the WIMPs energy region is possible, but low-noise light detectors are needed.