Development of liquid scintillator containing a zirconium complex for neutrinoless double beta decay experiment
Development of liquid scintillator containing a zirconium complex for neutrinoless double beta decay experiment
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DOI：
10.1016/j.nima.2013.06.043
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发表时间：
2013-12-21
影响因子：
1.4
通讯作者：
Ogawa, Izumi
中科院分区：
文献类型：
--
作者：
Fukuda, Yoshiyuki;Moriyama, Shigetaka;Ogawa, Izumi
为了新的无中微子双β衰变实验，研制了一种含有锆络合物的有机液体闪烁体。为了得到具有良好的能量分辨率(2.5 MeV时为4%)和低本底(0.1次/(T.年))并能监测数以吨计的靶同位素的探测器，我们选择了一种在苯甲醚中具有高溶解度(超过10wt%)的锆β-二酮络合物。但是，双酮配体的吸收峰与苯甲醚的发光峰重叠。因此，液体闪烁体的光产额与络合物的浓度成正比地下降。为了避免这个问题，我们合成了在β-二酮配体中引入-OC3H7或-OC2H5取代基的β-酮酯配合物，使其吸收峰移动到245 nm左右，比苯甲醚的发射峰(275 Nm)要短。然而，吸收峰的移动取决于闪烁溶剂的极性。因此，我们必须为液体闪烁体选择低极性的溶剂。我们还合成了一种高量子产率(30%)、发射波长(425 Nm)、在苯腈中的溶解度为5wt%的Zr-ODZ络合物。而Zr-ODZ络合物的吸收峰在240 nm左右。因此，最好使用发光波长比芳香族溶剂短的闪烁溶剂。(C)Elsevier B.V.出版的2013年
An organic liquid scintillator containing a zirconium complex has been developed for a new neutrinoless double beta decay experiment. In order to produce a detector that has good energy resolution (4% at 2.5 MeV) and low background (0.1 counts /(t. year)) and that can monitor tons of target isotope, we chose a zirconium beta-diketone complex having high solubility (over 10 wt%) in anisole. However, the absorption peak of the diketone ligand overlaps with the luminescence of anisole. Therefore, the light yield of the liquid scintillator decreases in proportion to the concentration of the complex. To avoid this problem, we synthesized a beta-keto ester complex introducing -OC3H7 or -OC2H5 substituent groups in the is beta-diketone ligand, which shifted the absorption peak to around 245 nm, which is shorter than the emission peak of anisole (275 nm). However, the shift of the absorption peak depends on the polarity of the scintillation solvent. Therefore we must choose a low polarity solvent for the liquid scintillator. We also synthesized a Zr-ODZ complex, which has a high quantum yield (30%) and good emission wavelength (425 nm) with a solubility 5 wt% in benzonitrile. However, the absorption peak of the Zr-ODZ complex was around 240 nm. Therefore, it is better to use the scintillation solvent which has shorter luminescence wavelength than that of the aromatic solvent. (C) 2013 Published by Elsevier B.V.