Measurement of muon-induced neutron yield at the China Jinping Underground Laboratory

【摘要】 Solar,terrestrial,and supernova neutrino experiments are subject to muon-induced radioactive background.The China Jinping Underground Laboratory（CJPL）,with its unique advantage of a 2400 m rock coverage and long distance from nuclear power plants,is ideal for MeV-scale neutrino experiments.Using a 1-ton prototype detector of the Jinping Neutrino Experiment（JNE）,we detected 3 43 high-energy cosmic-ray muons and（7.86±3.97）muon-induced neutrons from an 820.28-day dataset at the first phase of CJPL（CJPL-I）.Based on the muon-induced neutrons,we measured the corresponding muon-induced neutron yield in a liquid scintillator to be(3.44±1.86_stat.±0.76_syst.)×10^-4 μ^-1g^-1cm² at an average muon energy of 340 GeV.We provided the first study for such neutron background at CJPL.A global fit including this measurement shows a power-law coefficient of（0.75±0.02） for the dependence of the neutron yield at the liquid scintillator on muon energy.更多还原

【Abstract】 Solar,terrestrial,and supernova neutrino experiments are subject to muon-induced radioactive background.The China Jinping Underground Laboratory（CJPL）,with its unique advantage of a 2400 m rock coverage and long distance from nuclear power plants,is ideal for MeV-scale neutrino experiments.Using a 1-ton prototype detector of the Jinping Neutrino Experiment（JNE）,we detected 3 43 high-energy cosmic-ray muons and（7.86±3.97）muon-induced neutrons from an 820.28-day dataset at the first phase of CJPL（CJPL-I）.Based on the muon-induced neutrons,we measured the corresponding muon-induced neutron yield in a liquid scintillator to be(3.44±1.86_stat.±0.76_syst.)×10^-4 μ^-1g^-1cm² at an average muon energy of 340 GeV.We provided the first study for such neutron background at CJPL.A global fit including this measurement shows a power-law coefficient of（0.75±0.02） for the dependence of the neutron yield at the liquid scintillator on muon energy.更多还原