RICOCHET

The future RICOCHET neutrino experiment, to be deployed at the Institute Laue Langevin (ILL) research nuclear reactor, aims to exploit the Coherent Elastic Neutrino-Nucleus Scattering (CENNS) process to search for new physics in the electroweak sector. These include for instance the existence of sterile neutrinos and of new mediators, that could be related to the Dark Matter problem, and the possibility of Non Standard Interactions that would have tremendous implications on the global neutrino physics program. The Ricochet experiment will use a kg-scale cryogenic detector array, composed of 30 g-scale individual Ge and Zn crystals, with unparalleled particle identification capabilities down to the demonstrated 50 eV energy threshold. Thanks to these unique detector performance, Ricochet will have an unprecedented sensitivity to CENNS induced nuclear recoils down to the sub-100 eV energy range, where signs of new physics are expected to arise. The physics potential of RICOCHET at ILL is uniquely high. Our studies show that we will observe a daily rate of neutrino interactions of about 15 events/day combined with an expected signal-to-background ratio of 3, leading to a 5-sigma CENNS detection significance in only a couple of days. A percentage-level precision CENNS measurement, leading to unprecedented sensitivity to various exotic physics scenarios, will therefore be achieved after only 1 year of reactor ON data. Based on the complementary resources existing within the international collaboration, this ANR research program and requested funds will be dedicated to design, build and deploy the future RICOCHET low-energy neutrino observatory at the ILL research reactor by 2023.