Milan - An International Research Group Led by the National Research Council's Plasma Science and Technology Institute in Milan (CNR-ISTP) Provides a Major Contribution to Solving One of the Biggest Challenges in Nuclear Energy: Measuring the Power Achieved in New Fusion Reactors Based on the Deuterium-Tritium Reaction

To date, the only direct measurement technique for fusion power used in magnetic confinement reactors is to "count" the number of free neutrons generated from the fusion of two hydrogen isotopes—deuterium and tritium—that are commonly used as fuel in the reaction. When these reactants fuse, the resulting helium-5 nucleus decays into helium-4 and a free neutron with an energy of 14 MeV. The absolute count of these energetic neutrons provides a measure of the rate of fusion reactions that have occurred. However, this technique presents several difficulties: the emission of neutrons from an extended source such as a tokamak and their interaction with reactor materials require the use of complex simulation codes, as well as lengthy and costly calibration campaigns to validate these codes.

Today, the Italian-led study—conducted by CNR-ISTP in collaboration with the Department of Physics at the University of Milan-Bicocca and the University of Milan, the ENEA research center in Frascati, and other European institutions within the "GETART" project—identifies gamma rays emitted from the decay of helium-5 as a new and alternative method for measuring such power. The study is the subject of two scientific articles published in Physical Review C and Physical Review Letters. (9colonne)