Direct observation of coherent elastic antineutrino-nucleus scattering

• 成果类型: Article
• 署名作者: Ackermann, N.; Bonet, H.; Bonhomme, A.; Buck, C.; Fuelber, K.; Hakenmueller, J.; Hempfling, J.; Heusser, G.; Lindner, M.; Maneschg, W.; Ni, K.; Rank, M.; Rink, T.; Sanchez Garcia, E.; Stalder, I.; Strecker, H.; Wink, R.; Woenckhaus, J.
• 署名单位: Max Planck Society; Universites de Strasbourg Etablissements Associes; Universite de Strasbourg; Centre National de la Recherche Scientifique (CNRS); Duke University; Helmholtz Association; Karlsruhe Institute of Technology; Swiss Federal Institutes of Technology Domain; Paul Scherrer Institute
• 刊物名称: Nature
• ISSN/ISSBN: 0028-1229
• DOI: 10.1038/s41586-025-09322-2
• 发表日期: 2025-07-31
• 关键词: ray induced neutrons; energy-spectrum; neutrino

摘要

Neutrinos are elementary particles that interact only very weakly with matter. Neutrino experiments are, therefore, usually big, with masses in the multi-tonne range. The thresholdless interaction of coherent elastic scattering of neutrinos on atomic nuclei leads to greatly enhanced interaction rates, which allows for much smaller detectors. The study of this process gives insights into physics beyond the Standard Model of particle physics. The CONUS+ experiment1 was designed to first detect elastic neutrino-nucleus scattering in the fully coherent regime with low-energy neutrinos produced in nuclear reactors. For this purpose, semiconductor detectors based on high-purity germanium crystals with extremely low-energy thresholds were developed2. Here we report the first observation of a neutrino signal with a statistical significance of 3.7 sigma from the CONUS+ experiment, operated at the nuclear power plant in Leibstadt, Switzerland. In 119 days of reactor operation (395 +/- 106) neutrinos were measured compared with a predicted number from calculations assuming Standard Model physics of (347 +/- 59) events. With increased precision, there is potential for fundamental discoveries in the future. The CONUS+ results in combination with other measurements of this interaction channel might therefore mark a starting point for a new era in neutrino physics.