Researchers from Brookhaven National Laboratory, including A. A. Sonzogni, R. J. Lorek, A. Mattera, and E. A. McCutchan, have revisited decades-old data to explore its potential relevance to a modern nuclear energy puzzle. Their work, published in the journal Physical Review C, focuses on the Reactor Antineutrino Anomaly, a discrepancy in the number of antineutrinos observed from nuclear reactors compared to theoretical predictions.
In the 1970s, scientists at Oak Ridge National Laboratory conducted extensive measurements of decay heat, the energy released following the fission of uranium-235 and plutonium isotopes (239 and 241). This research was initially aimed at understanding potential loss of coolant accidents in nuclear reactors. Decay heat primarily consists of energy from beta-minus decay (which produces electrons and antineutrinos) and gamma radiation from excited nuclear levels.
The researchers analyzed this historical data to see if it could shed light on the Reactor Antineutrino Anomaly, a roughly 5% deficit in observed antineutrinos first noted in 2011. Using nuclear databases, they calculated the ratio of electron spectra under equilibrium conditions for different isotopes. Their findings showed better agreement with recent measurements for the uranium-235 to plutonium-239 ratio but found discrepancies for other isotope pairs compared to older measurements.
The study concludes that to resolve these inconsistencies and better understand the Reactor Antineutrino Anomaly, new experimental campaigns are needed. These should employ high-resolution electron spectrometers and precise fission normalization procedures. For the energy sector, this research underscores the importance of accurate antineutrino measurements in nuclear reactor operations and safety assessments. Improved understanding of antineutrino emissions could enhance reactor monitoring, design, and safety protocols, contributing to more efficient and secure nuclear energy production.
The research was published in the journal Physical Review C, a publication of the American Physical Society.
This article is based on research available at arXiv.