Reflectance of VUV-sensitive SiPM surfaces in liquid xenon
Reflectance of VUV-sensitive SiPM surfaces in liquid xenon
复制标题
液态氙中 VUV 敏感 SiPM 表面的反射率
DOI：
10.1016/j.nima.2018.09.142
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
T. Ziegler
中科院分区：
文献类型：
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作者：
M. Wagenpfeil;T. Ziegler
nEXO实验将运行一个超低本底时间投影室，其中装有5吨同位素富集的液体氙（LXe），用于寻找Xe-136中的无中微子双β衰变。探测器将使用4平方米的硅光电倍增管（SiPM），工作温度约为-104 ° C，以收集闪烁光。对背景水平、光收集效率和SiPM性能有严格的要求，以设定最严格的半衰期限制。探测到0 ν β β衰变将对中微子物理学产生广泛的影响。SiPM需要对178 nm处的真空紫外线闪烁光敏感，这对于现成的SiPM是没有给出的。nEXO采用的SiPM性能要求是（其中包括）在178 nm处至少15%的光子探测效率，小于20%的相关雪崩概率和低暗率。此外，LEXO中SiPM表面的VUV反射率是最佳光收集的重要参数，因此也是nEXO能量分辨率的重要参数。我们目前的测量与国家的最先进的VUV敏感的SiPM专注于液体氙的表面VUV反射率。
The nEXO experiment will operate an ultra-low background time projection chamber filled with 5 t of isotopically enriched liquid xenon (LXe) for the search for the neutrinoless double beta decay in Xe-136. The detector will use 4 m 2 of silicon photomultipliers (SiPMs) operated at about− 104∘ C to collect the scintillation light. There are strong requirements on the background levels, light collection efficiency and SiPM performance to set the most stringent limits on the half-life. Detecting the 0 ν β β-decay would have wide-spread implications for neutrino physics. The SiPMs need to be sensitive to the vacuum-ultraviolet scintillation light of LXe at 178 nm which is not given for off-the-shelf SiPMs. The SiPM performance requirements adopted by nEXO are (among others) a photon detection efficiency of at least 15% at 178 nm, a correlated avalanche probability of less than 20% and a low dark-rate. Additionally, the VUV-reflectance of the SiPM surface in LXe is an important parameter for optimal light collection and thus the energy resolution of nEXO. We present measurements with state-of-the-art VUV-sensitive SiPMs focusing on the surface VUV-reflectance in liquid xenon.