Searching for $^{76}$Ge neutrinoless double beta decay with the CDEX-1B experiment

作者：B. T. Zhang, Wang, J. Z., L. T. Yang, Yue, Q., K. J. Kang, Y. J. Li, Haipeng An, C. Greeshma, J. P. Chang, Y. H. Chen, J. P. Cheng, W. H. Dai, Z. Deng, C. H. Fang, Xiaowan Geng, H. Gong, Q. J. Guo, X. Y. Guo, L. He, S. M. He, Jiawen Hu, H. X. Huang, T. C. Huang, H. T. Jia, Xiaolan Jiang, S. Karmakar, Hui Li, J. M. Li, J. Li, Q. Y. Li, R. M. J. Li, X. Q. Li, Y. L. Li, Liang Yu, Beining Liao, F. K. Lin, S. T. Lin, J. X. Liu, S. K. Liu, Y. D. Liu, Y. Liu, Y. Y. Liu, Z. Z. Liu, Haijing Ma, Y. C. Mao, Q. Y. Nie, J. H. Ning, H. Pan, N. C. Qi, J. Ren, Xichao Ruan, Zhiyong She, M. K. Singh, T. X. Sun, C. J. Tang, W. Y. Tang, Y. Tian, G. F. Wang, L. Wang, Qing Wang, Y. F. Wang, Yuhang Wang, H. T. Wong, S. Y. Wu, Y. C. Wu, H. Y. Xing, R. Xu, Y. Xu, T. Xue, Y. L. Yan, N. Yi, C. X. Yu, H. J. Yu, J. F. Yue, M. Zeng, Zhenling Zeng, F. S. Zhang, L. Zhang, Z. H. Zhang, Z. Y. Zhang, K. K. Zhao, M. G. Zhao, J. F. Zhou, Z. Y. Zhou, J. J. Zhu · 发表于：arXiv (Cornell University) · 年份：2023 · DOI：10.48550/arxiv.2305.00894 · 被引用次数：3 · 研究领域：Neutrino Physics Research、Particle physics theoretical and experimental studies、Dark Matter and Cosmic Phenomena

We operated a p-type point contact high purity germanium (PPCGe) detector (CDEX-1B, 1.008 kg) in the China Jinping Underground Laboratory (CJPL) for 500.3 days to search for neutrinoless double beta ($0νββ$) decay of $^{76}$Ge. A total of 504.3 kg$\cdot$day effective exposure data was accumulated. The anti-coincidence and the multi/single-site event (MSE/SSE) discrimination methods were used to suppress the background in the energy region of interest (ROI, 1989$-$2089 keV for this work) with a factor of 23. A background level of 0.33 counts/(keV$\cdot$kg$\cdot$yr) was realized. The lower limit on the half life of $^{76}$Ge $0νββ$ decay was constrained as $T_{1/2}^{0ν}\ > \ {1.0}\times 10^{23}\ \rm yr\ (90\% \ C.L.)$, corresponding to the upper limits on the effective Majorana neutrino mass: $\langle m_{ββ}\rangle < $3.2$-$7.5$\ \mathrm{eV}$.