Evidence of Coherent Elastic Neutrino-Nucleus Scattering with COHERENT's Germanium Array

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We report the first detection of coherent elastic neutrino-nucleus scattering (CEvNS) on natural germanium, measured at the Spallation Neutron Source at Oak Ridge National Laboratory.

• The Ge-Mini detector of the COHERENT collaboration employs large-mass, low-noise, high-purity germanium spectrometers, enabling excellent energy resolution, and an analysis threshold of 1.5 keV electron-equivalent ionization energy.
• We observe a on-beam excess of 20.6 +7.1 -6.3 counts with a total exposure of 10.22 GWhkg and we reject the no-CEvNS hypothesis with 3.9 sigma significance.
• The result agrees with the predicted standard model of particle physics signal rate within 2 sigma.