Abstract
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 an on-beam excess of 20.6-6.3+7.1 counts with a total exposure of 10.22 GWhkg, and we reject the no-CEvNS hypothesis with 3.9σ significance. The result agrees with the predicted standard model of particle physics signal rate within 2σ.
| Original language | English |
|---|---|
| Article number | 231801 |
| Journal | Physical Review Letters |
| Volume | 134 |
| Issue number | 23 |
| DOIs | |
| State | Published - Jun 13 2025 |
Funding
The COHERENT Collaboration acknowledges the generous resources provided by the ORNL Spallation Neutron Source, a DOE Office of Science User Facility. Laboratory Directed Research and Development funds from ORNL also supported this project. We acknowledge support from U.S. Department of Energy Office of Science and the National Science Foundation. The Ge-Mini array detectors and hardware were acquired through National Science Foundation Major Research Instrumentation Award No. 1920001. We also acknowledge support from the Alfred P. Sloan Foundation, the Consortium for Nonproliferation Enabling Capabilities, and the Korea National Research Foundation (Grant No. NRF 2022R1A3B1078756). This research used the Oak Ridge Leadership Computing Facility, which is a DOE Office of Science User Facility. We also acknowledge support from Ministry of Science and Higher Education of the Russian Federation, Project “New Phenomena in Particle Physics and the Early Universe,” FSWU-2023-0073. We thank Mirion Technologies of Meriden, Connecticut, for guidance and support with the detectors.