The NUCLEUS Collaboration aims to measure the coherent elastic scattering of neutrinos on nuclei using reactor (anti)neutrinos, in the fully coherent regime.
The scattering of a large flux of (anti)neutrinos produced by two nuclear reactors is detected on a network of cryogenic detectors operated at around 10 mK.
The experiment will be installed at the Chooz nuclear power plant in France, operated by Électricité de France.
NUCLEUS uses single, gram-scale crystals operated at mK temperatures as cryogenic calorimeters,
instrumented with thin tungsten film Transition Edge Sensors (TES) and read-out with Superconducting Quantum Interference Devices (SQUID) amplifiers. The same technology is used in the CRESST dark-matter experiment.
Two 3x3 arrays of CaWO4 crystals and Al2O3 crystals, mounted in a TES-instrumented silicon inner beaker and surrounded by a Ge outer veto system will create a fiducial volume for the cryogenic detection system.
The cryogenic detector system is inserted in a cylindrical dry cryostat, surrounded by an external passive/active shielding system composed of a muon veto, alternating layers of mechanical structure, lead and borated polyethylene.
The experiment will be located at the "Very Near Site" (VNS), a new experimental site developed at the Électricité de France (EdF) Chooz commercial nuclear power plant, in the basement of building situated between the two rectors of the plant, each with a thermal power of 4.25 MW, at 72 m and 102 m distance from the reactors.