Search for double beta decay of 136Xe to the $$ {0}_1^{+} $$ excited state of 136Ba with PandaX-4T

作者：Lingyin Luo, Zihao Bo, Wei Chen, Xun Chen, Yunhua Chen, Zhaokan Cheng, Xiangyi Cui, Yingjie Fan, Deqing Fang, Zhixing Gao, Lisheng Geng, Karl Giboni, Xunan Guo, Xuyuan Guo, Zichao Guo, Chencheng Han, Ke Han, Changda He, Jinrong He, Di Huang, Houqi Huang, J. Huang, Ruquan Hou, Yu Hou, Xiangdong Ji, Xiangpan Ji, Yonglin Ju, Chenxiang Li, Tao Li, Jiafu Li, Mingchuan Li, Shuaijie Li, Zhiyuan Li, Qing Lin, Jianglai Liu, Congcong Lu, Xiaoying Lü, Yunyang Luo, Wenbo Ma, Y. G., Yajun Mao, Yue Meng, Xuyang Ning, Binyu Pang, Ningchun Qi, Zhicheng Qian, Xiangxiang Ren, Dong Shan, Xiaofeng Shang, Xiyuan Shao, Guofang Shen, Manbin Shen, Wenliang Sun, Yi Tao, Anqing Wang, Guanbo Wang, Hao Wang, Jiamin Wang, Lei Wang, Meng Wang, Qiu-Hong Wang, Shaobo Wang, Siguang Wang, W. Wang, Xiuli Wang, W. Wang, Xiuli Wang, Xu Wang, Zhou Wang, Yuehuan Wei, Weihao Wu, Yuan Wu, Mengjiao Xiao, Xiang Xiao, Kaizhi Xiong, Yifan Xu, Xiyu Yan, Binbin Yan, Xiyu Yan, Yong Yang, Peihua Ye, Chunxu Yu, Ying Yuan, Zhe Yuan, Youhui Yun, Xinning Zeng, Minzhen Zhang, P. Zhang, Shibo Zhang, Shu Zhang, Tao Zhang, Wei Zhang, Yuanyuan Zhang, Yingxin Zhang, Yuanyuan Zhang, Li Zhao, Jifang Zhou, Jiaxu Zhou, Ning Zhou, Xiaopeng Zhou, Yubo Zhou, Zhizhen Zhou · 发表于：Journal of High Energy Physics · 年份：2025 · DOI：10.1007/jhep05(2025)089 · 被引用次数：2 · 研究领域：Neutrino Physics Research、Nuclear physics research studies、Particle physics theoretical and experimental studies

A bstract We perform a search of double beta decay of 136 Xe to the excited state, $$ {0}_1^{+} $$ 0 1 + , of 136 Ba (2 νββ - $$ {0}_1^{+} $$ 0 1 + ), using the dual-phase xenon detector of PandaX-4T with the first 94.9-day commissioning data. The multi-site events are reconstructed up to the MeV energy scale, which helps to improve the background model significantly. The background contribution from the stainless steel platform outside PandaX-4T cryostat is evaluated for the first time. No significant evidence for 2 νββ - $$ {0}_1^{+} $$ 0 1 + is observed, resulting in a lower limit on half-life of 7 . 5 × 10 22 yr at the 90% confidence level. This is the first experimental limit on such a rare decay in a natural xenon-based detector.