Studies on double beta decay processes in ${}^{106}$Cd were performed by using a cadmium tungstate scintillator enriched in ${}^{106}$Cd at 66% (${}^{106}$CdWO${}_4$) with two CdWO${}_4$ scintillation counters (with natural Cd composition). No effect was observed in the data that accumulated over 26,033 h. New improved half-life limits were set on the different channels and modes of the ${}^{106}$Cd double beta decay at level of $lim{T}_{1/2}\sim {10}^{20}-{10}^{22}$ yr. The limit for the two neutrino electron capture with positron emission in ${}^{106}$Cd to the ground state of ${}^{106}$Pd, $T_{1/2}^{2\nu \mathrm{EC}{\beta }^{+}}\ge 2.1\times {10}^{21}$ yr, was set by the analysis of the ${}^{106}$CdWO${}_4$ data in coincidence with the energy release 511 keV in both CdWO${}_4$ counters. The sensitivity approaches the theoretical predictions for the decay half-life that are in the range $T_{1/2}\sim {10}^{21}-{10}^{22}$ yr. The resonant neutrinoless double-electron capture to the 2718 keV excited state of ${}^{106}$Pd is restricted at the level of $T_{1/2}^{0\nu 2\mathrm{K}}\ge 2.9\times {10}^{21}$ yr.

中文翻译：

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用丰富的106CdWO4晶体闪烁体与CdWO4闪烁计数器同时搜索106Cd的双Beta衰减

双β衰变过程的研究。 ${}^{106}$使用富集钨酸镉的闪烁体进行镉测定 ${}^{106}$镉含量66％（${}^{106}$镉${}_4$）和两个CdWO${}_4$闪烁计数器（具有天然Cd成分）。在超过26,033小时内累积的数据中未观察到任何影响。新的改进的半衰期限制是针对不同的通道和模式设置的${}^{106}$镉双β衰减水平 $林{Ť}_{\mathrm{1个}/2}〜{10}^{20}-{10}^{22}$年。正电子发射中两个中微子电子俘获的极限。${}^{106}$镉到基态 ${}^{106}$钯 ${Ť}_{\mathrm{1个}/2}^{2\nu \mathrm{欧共体}{\beta }^{+}}\ge 2.1\times {10}^{21}$ yr，是通过对 ${}^{106}$镉${}_4$ 与两个CdWO中的能量释放511 keV一致的数据${}_4$柜台。灵敏度接近范围内衰减半衰期的理论预测${Ť}_{\mathrm{1个}/2}〜{10}^{21}-{10}^{22}$年。共振中微子双电子俘获到2718 keV激发态${}^{106}$Pd限制在 ${Ť}_{\mathrm{1个}/2}^{0\nu 2\mathrm{ķ}}\ge 2.9\times {10}^{21}$ 年。