Physicists have successfully detected neutrinos emitted from a nuclear reactor utilizing a remarkably small device, significantly lighter than the traditional large-scale neutrino detectors. This breakthrough method could revolutionize the testing of established physics theories and enhance the detection of numerous neutrinos produced during the collapse of stars.
Kate Scholberg, a physicist from Duke University based in Durham, North Carolina, expressed her enthusiasm about the achievement, noting the results as exceptionally striking. The details of this experiment, named CONUS+, were published on July 30 in the journal Nature.
Elusive Targets
Support Science Journalism
If you appreciate this content, please consider supporting our distinguished journalism by subscribing. Your subscription helps sustain future reporting on significant discoveries and ideas that are shaping our world today.
Neutrinos are fundamental particles that lack an electrical charge and rarely interact with other matter, which makes them incredibly challenging to detect. Typically, neutrino detectors capture these elusive particles by observing the light flashes produced when a neutrino collides with an electron, proton, or neutron. Given the rarity of these collisions, detectors are usually massive, weighing tons or even thousands of tons, to accumulate a sufficient amount of neutrinos.
Scholberg and her team initially demonstrated this mini-detector approach in 2017, which was used to capture neutrinos from an accelerator at Oak Ridge National Laboratory in Tennessee. These particles had slightly higher energy levels than those produced in reactors, making the detection of reactor neutrinos a tougher challenge. However, these lower-energy neutrinos provide a more accurate test of the standard model of physics.
The COHERENT detector pioneered by Scholberg’s team was the first to utilize a phenomenon known as coherent scattering, where a neutrino scatters off an entire atomic nucleus rather than just its individual particles.
Christian Buck, a leader of the CONUS collaboration and a physicist at the Max Planck Institute for Nuclear Physics in Heidelberg, Germany, explains that coherent scattering leverages the wave-like nature of particles—the lower the energy of the particles, the longer their wavelengths. If a neutrino’s wavelength is similar to the size of a nucleus, “the neutrino perceives the nucleus as a single unit, not discerning its internal components,” Buck says. This interaction doesn’t affect the subatomic particles but causes the nucleus to recoil, imparting a small amount of energy into the detector.
Tracking Nuclear Reactions
Coherent scattering happens over 100 times more frequently than the interactions observed in other detectors, which typically see a nucleus as a cluster of smaller particles. This increased efficiency allows for the construction of smaller detectors that still monitor a comparable number of particles over the same period. “Now, building detectors on the kilogram scale is feasible,” Buck notes.
However, the energy deposited by the neutrinos at the nucleus site is minimal. The effect of a neutrino on a nucleus is akin to the impact of a ping-pong ball on a ship, Buck describes—until recently, this has been exceedingly difficult to measure.
The CONUS detector consists of four modules of pure germanium, each weighing 1 kilogram. It was initially set up at a nuclear reactor in Germany from 2018 until the reactor’s closure in 2022. The detector, now upgraded to CONUS+, was relocated to the Leibstadt nuclear power plant in Switzerland. Since its move, the team has recorded approximately 395 collision events over 119 days of operation, aligning with standard model predictions.
Following the landmark 2017 results obtained with caesium iodide detectors, Scholberg’s team replicated these findings with detectors composed of argon and germanium. Last year, two separate experiments initially aimed at detecting dark matter picked up signs of low-energy coherent scattering from neutrinos emitted by the Sun. Scholberg mentions that the standard model provides precise predictions on the rate of coherent scattering and its variation across different types of atomic nuclei, underscoring the importance of comparing outcomes across various detecting materials. Enhanced sensitivity of this technique could also advance solar science significantly.
Researchers believe that while coherent scattering may not entirely replace existing neutrino detection technologies, it can detect all three known types of neutrinos (and their antiparticles) down to low energies, which some methods cannot. This capability could complement large-scale detectors designed to capture higher-energy neutrinos, such as the Hyper-Kamiokande observatory currently being built in Japan.
*This article is reproduced with permission and was first published on July 30, 2025.*
Similar Posts
- Breaking: Record-Breaking Neutrino Detected in the Mediterranean!
- Flamanville EPR Halts Again: Continual Delays Plague French Nuclear Project
- Spacetime Sounds Uncovered! Why We Must Continue Listening
- Breaking News: Large Hadron Collider Unveils Mysterious Antimatter Secrets!
- Muon Anomaly Mystery: Is the Particle Physics Enigma Finally Solved?
Cameron Aldridge combines a scientific mind with a knack for storytelling. Passionate about discoveries and breakthroughs, Cameron unravels complex scientific advancements in a way that’s both informative and entertaining.