The LUX–ZEPLIN collaboration recently reported a single nuclear‑recoil candidate at 248 ± 23 (stat) ± 23 (syst) keV (nuclear recoil energy). This energy is high compared with where most dark‑matter and neutrino signals appear. The paper asks whether coherent elastic neutrino–nucleus scattering (CEνNS) — a neutrino bouncing off an entire xenon nucleus — could produce that lone event. The authors conclude it cannot, for all elastic‑scattering scenarios they tested.

To reach this conclusion the researchers compared expectations from known and hypothetical neutrino sources to the LZ data. They used the LZ exposure (2.84 ton·yr), the experiment’s efficiency and energy resolution, and nuclear form factors to predict recoil spectra. Kinematic limits rule out solar neutrinos and make the diffuse supernova background negligible at the required recoil energy. Atmospheric neutrinos are the only standard source energetic enough, but their flux falls rapidly with energy and the coherent nuclear response is strongly suppressed at the large momentum transfer needed to make such a high recoil. In the Standard Model they estimate the expected number of events in the signal bin to be essentially zero (about 2×10^−6).

The authors also tested beyond‑Standard‑Model possibilities that could boost the elastic scattering rate. They considered a new vector mediator (which interferes with the Standard Model interaction) and a scalar mediator (which adds without interference). To get one event in the 225–271 keV signal window requires enormously larger scattering rates. Those same new interactions would then predict roughly 10^5 events at much lower recoil energies, where LZ sees no excess. In short, the couplings needed to explain the lone high‑energy event would overproduce low‑energy recoils and contradict the observed spectrum.