论文标题
搜索$^{136} $ XE的中准四元β衰减在xmass-i中
Search for neutrinoless quadruple beta decay of $^{136}$Xe in XMASS-I
论文作者
论文摘要
搜索$^{136} $ XE的中性s中性四倍β衰减，使用$ \ rm 327 \进行了液体-Xenon检测器Xmass-i； kg \ times 800.0 \;曝光的天$。基于闪烁衰减时间常数的脉冲形状歧视，该衰减时间常数区分了$γ$ - 包括信号和$β$ - 砂，用于增强搜索灵敏度。通过精确的背景评估，从能源拟合中观察到没有显着的信号过剩，我们将半寿命的下限设置为3.7 $ \ times $ 10 $^{24} $年$ prustice fustrump。这是$^{136} $ xe的中性四元β衰减的第一个实验约束。
A search for the neutrinoless quadruple beta decay of $^{136}$Xe was conducted with the liquid-xenon detector XMASS-I using $\rm 327\; kg \times 800.0 \; days$ of the exposure. The pulse shape discrimination based on the scintillation decay time constant which distinguishes $γ$-rays including the signal and $β$-rays was used to enhance the search sensitivity. No significant signal excess was observed from the energy spectrum fitting with precise background evaluation, and we set a lower limit of the half life of 3.7 $\times$ 10$^{24}$ years at 90$\%$ confidence level. This is the first experimental constraint of the neutrinoless quadruple beta decay of $^{136}$Xe.
