CENNS · Probing new physics with Coherent Elastic Neutrino-Nucleus Scattering and a tabletop experiment

Ever since the Higgs boson was discovered at the LHC in 2012, we had the confirmation that the Standard Model (SM) of particle physics has to be extended. In parallel, the long lasting Dark Matter (DM) problem, supported by a wealth of evidence ranging from precision cosmology to local astrophysical observations, has been suggesting that new particles should exist. Unfortunately, neither the LHC nor the DM dedicated experiments have significantly detected any exotic signals pointing toward a particular new physics extension of the SM so far.With this proposal, I want to take a new path in the quest of new physics searches by providing the first high-precision measurement of the neutral current Coherent Elastic Neutrino-Nucleus Scattering (CENNS). By focusing on the sub-100 eV CENNS induced nuclear recoils, my goal is to reach unprecedented sensitivities to various exotic physics scenarios with major implications from cosmology to particle physics, beyond the reach of existing particle physics experiments. These include for instance the existence of sterile neutrinos and of new mediators, that could be related to the DM problem, and the possibility of Non Standard Interactions that would have tremendous implications on the global neutrino physics program. To this end, I propose to build a kg-scale cryogenic tabletop neutrino experiment with outstanding sensitivity to low-energy nuclear recoils, called CryoCube, that will be deployed at an optimal nuclear reactor site. The key feature of this proposed detector technology is to combine two target materials: Ge-semiconductor and Zn-superconducting metal. I want to push these two detector techniques beyond the state-of-the-art performance to reach sub-100 eV energy thresholds with unparalleled background rejection capabilities. As my proposed CryoCube detector will reach a 5-sigma level CENNS detection significance in a single day, it will be uniquely positioned to probe new physics extensions beyond the SM.