Basic research for search for neutrino-less double beta decay of 136Xe in KamLAND

我们在卡姆兰德进行了研究和开发，以实现世界上最高灵敏度的双β衰变搜索。本研究的前半部分，我们研制了用于卡姆兰德的微型气球，微型气球的安装方法，载氙液闪体的填充方法。在技术建立后，我们制作了微型气球，安装了微型气球，并填充了氙气液体闪烁体。然后，我们开始了卡姆兰德-禅宗实验。卡姆兰德-禅宗合作报告了78天的观测数据的第一个结果。~lt；136&gt；^Xe的双中微子双β衰变半衰期为2.38±0。02(统计)±0。14(系统)×10^21年。~lt；136&gt；^Xe的无中微子双β衰变下限为&5.7×10^24年。

We performed research and developments to realize double beta decay search in KamLAND with world highest sensitivity. First half of this research, we developed mini-balloon which is used in KamLAND, method of installation of mini-balloon, method of filling of xenon loaded liquid scintillator. After the establishment of techniques, we made mini-balloon, installed mini-balloon, and filled xenon loaded liquid scintillator. Then, we started KamLAND-Zen experiment.KamLAND-Zen collaboration reported first results with 78 days of observation data. The two-neutrino double beta decay half-life of <136>^Xe is 2. 38±0. 02(stat.)±0. 14(syst.)× 10^21 year. The lower limit of neutrino-less double beta decay half-life of <136>^Xe is > 5. 7× 10^24 year.