[Chen, Wei] Univ Chinese Acad Sci, Sch Nucl Sci & Technol, Beijing 100049, Peoples R China.^[Yang, Zhong;Pang, Longgang;Wang, Xin-Nian] Cent China Normal Univ, Key Lab Quark & Lepton Phys, MOE, Wuhan 430079, Peoples R China.^[Yang, Zhong;Pang, Longgang;Wang, Xin-Nian] Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.^[He, Yayun] South China Normal Univ, Guangdong Prov Key Lab Nucl Sci, Inst Quantum Matter, Guangzhou 510006, Peoples R China.^[Luo, Tan] Univ Santiago Compostela, Inst Galego Fis Altas Enerxias IGFAE, Galicia, Spain.^[Wang, Xin-Nian] Lawrence Berkeley Natl Lab, Nucl Sci Div, MS 70R0319, Berkeley, CA 94720 USA.