The article “Measurement of Reactor Neutrino Oscillation with the First JUNO Data,” published in the prestigious journal Nature, marks the scientific debut of the Jiangmen Underground Neutrino Observatory (JUNO), one of the world’s leading international experiments dedicated to the study of neutrinos. The study was also selected as the cover paper for the June 10, 2026 issue, an honor reserved for the most significant scientific contributions.

Among the authors are Antonio Cammi, Professor in the Department of Energy at Politecnico di Milano, and Lorenzo Loi, a PhD candidate in the Department, both members of the JUNO Collaboration, the international partnership that brings together hundreds of researchers working on the construction, operation, and scientific exploitation of the observatory.

A Result Published in Nature

Founded in 1869, Nature is one of the world’s most prestigious and selective scientific journals. It publishes research representing major advances across all scientific disciplines and serves as an international benchmark for the dissemination of groundbreaking scientific discoveries.

The selection of the article as the cover paper highlights the significance of the achievement by the JUNO Collaboration and the scientific community’s strong interest in the experiment’s potential.

JUNO’s First Measurements of Neutrino Oscillations

The paper presents JUNO’s first physics results, obtained using just 59 days of data collection following the completion of the detector in August 2025.

The analysis has produced the most precise measurement to date of two fundamental parameters governing neutrino oscillations, the quantum phenomenon by which neutrinos change from one flavor to another as they travel. The achieved precision is approximately 1.6 times better than the combined precision of all previous experiments.

Why This Result Matters

Neutrinos are among the most elusive fundamental particles in the Universe. Because they interact only weakly with matter, they are extremely difficult to detect. Yet understanding their properties is essential for uncovering the fundamental laws governing matter and the evolution of the Universe.

Measuring neutrino properties with unprecedented precision enables scientists to test the theory of neutrino oscillations, determine the neutrino mass ordering, and search for possible signs of physics beyond the Standard Model. The results published in Nature demonstrate that JUNO has already achieved its expected performance, laying the foundation for an extensive scientific program that will investigate neutrinos originating from nuclear reactors, the Sun, the Earth’s atmosphere, supernovae, and the Earth’s interior over the coming years.

The Department of Energy’s Contribution

The Department of Energy contributes to the JUNO Collaboration through the research group led by Professor Antonio Cammi, which also includes PhD candidate Lorenzo Loi. The group’s work has focused primarily on the development of models to simulate the energy spectrum of reactor antineutrinos produced by nuclear power plants. The group is part of the Italian National Institute for Nuclear Physics (INFN), which participates in JUNO through several divisions across Italy, including the Milan-Bicocca Section, led by Professor Monica Sisti, with which the Politecnico di Milano research group is affiliated.