The $$\nu $$ ν -cleus experiment: a gram-scale fiducial-volume cryogenic detector for the first detection of coherent neutrino–nucleus scattering

Abstract

Abstract We discuss a small-scale experiment, called $$\nu $$ ν -cleus, for the first detection of coherent neutrino–nucleus scattering by probing nuclear-recoil energies down to the 10 eV regime. The detector consists of low-threshold CaWO $$_4$$ 4 and Al $$_2$$ 2 O $$_3$$ 3 calorimeter arrays with a total mass of about 10 g and several cryogenic veto detectors operated at millikelvin temperatures. Realizing a fiducial volume and a multi-element target, the detector enables active discrimination of $$\gamma $$ γ , neutron and surface backgrounds. A first prototype Al $$_2$$ 2 O $$_3$$ 3 device, operated above ground in a setup without shielding, has achieved an energy threshold of $${\sim }20$$ ∼ 20 eV and further improvements are in reach. A sensitivity study for the detection of coherent neutrino scattering at nuclear power plants shows a unique discovery potential (5 $$\sigma $$ σ ) within a measuring time of $${\lesssim }2$$ ≲ 2 weeks. Furthermore, a site at a thermal research reactor and the use of a radioactive neutrino source are investigated. With this technology, real-time monitoring of nuclear power plants is feasible.