1. Searching for $^{76}$Ge neutrinoless double beta decay with the CDEX-1B experiment
- Author
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Zhang, B. T., Wang, J. Z., Yang, L. T., Yue, Q., Kang, K. J., Li, Y. J., An, H. P., C., Greeshma, Chang, J. P., Chen, Y. H., Cheng, J. P., Dai, W. H., Deng, Z., Fang, C. H., Geng, X. P., Gong, H., Guo, Q. J., Guo, X. Y., He, L., He, S. M., Hu, J. W., Huang, H. X., Huang, T. C., Jia, H. T., Jiang, X., Karmakar, S., Li, H. B., Li, J. M., Li, J., Li, Q. Y., Li, R. M. J., Li, X. Q., Li, Y. L., Liang, Y. F., Liao, B., Lin, F. K., Lin, S. T., Liu, J. X., Liu, S. K., Liu, Y. D., Liu, Y., Liu, Y. Y., Liu, Z. Z., Ma, H., Mao, Y. C., Nie, Q. Y., Ning, J. H., Pan, H., Qi, N. C., Ren, J., Ruan, X. C., She, Z., Singh, M. K., Sun, T. X., Tang, C. J., Tang, W. Y., Tian, Y., Wang, G. F., Wang, L., Wang, Q., Wang, Y. F., Wang, Y. X., Wong, H. T., Wu, S. Y., Wu, Y. C., Xing, H. Y., Xu, R., Xu, Y., Xue, T., Yan, Y. L., Yi, N., Yu, C. X., Yu, H. J., Yue, J. F., Zeng, M., Zeng, Z., Zhang, F. S., Zhang, L., Zhang, Z. H., Zhang, Z. Y., Zhao, K. K., Zhao, M. G., Zhou, J. F., Zhou, Z. Y., and Zhu, J. J.
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Nuclear Experiment ,High Energy Physics - Experiment ,Physics - Instrumentation and Detectors - Abstract
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 ($0\nu\beta\beta$) 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 $0\nu\beta\beta$ decay was constrained as $T_{1/2}^{0\nu}\ > \ {1.0}\times 10^{23}\ \rm yr\ (90\% \ C.L.)$, corresponding to the upper limits on the effective Majorana neutrino mass: $\langle m_{\beta\beta}\rangle < $3.2$-$7.5$\ \mathrm{eV}$., Comment: 11 pages, 12 figures, 2 tables. Version updated to match CPC version
- Published
- 2023
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