High significance measurement of reactor coherent elastic neutrino-nucleus scattering on germanium by CONUS+

We report the most precise measurement to date of coherent elastic neutrino-nucleus scattering (CE$ν$NS) from reactor antineutrinos using the CONUS+ high-purity germanium detectors at the Leibstadt nuclear power plant. With an exposure of 1296 kg·days reactor-on, a blind likelihood analysis yields 1555 ± 152 CE$ν$NS events, with a significance of 10.2 $σ$, in agreement with the Standard Model expectation of 1701 ± 198 events within 0.6 standard deviations. The result also determines the weak mixing angle at a momentum transfer of about 10 MeV, sin²θW = 0.225 ± 0.022, consistent with the Standard Model prediction.