Resolving the LMA-dark NSI degeneracy with coherent neutrino–nucleus scattering

Not scheduled
Asynchronous Talk Neutrino Physics Neutrino Physics Session 2


Mr Mariano Chaves (University of Campinas)


In the presence of non-standard neutrino interactions (NSI), a degeneracy exists
in neutrino oscillation data, which involves the flipping of the octant of the mixing angle $\theta_{13}$ and the type of the neutrino mass ordering. In this article, we revisit the status of this degeneracy in the light of recent data on coherent elastic neutrino–nucleus scattering (CEνNS) from the COHERENT experiment. For general relative couplings to up and down quarks, the degeneracy is disfavoured at the 2$\sigma$ level by the latest data but remains at a higher confidence level. We investigate the requirements of future CE$\nu$NS measurements to resolve the degeneracy with high significance. We find that a measurement involving both, electron and muon neutrino flavours and a target with a neutron-to-proton ratio close to 1 is required. For example, an experiment with a silicon target at the European Spallation Source can resolve the degeneracy at more than 4$\sigma$ for arbitrary relative couplings to up and down quarks.

Primary authors

Mr Mariano Chaves (University of Campinas) Prof. Thomas Schwetz (Karlsruhe Institute of Technology)

Presentation materials