Scientists have made a significant breakthrough in understanding plasma confinement — a key challenge on the path to nuclear fusion, a potential source of clean and virtually unlimited energy. This process occurs in ultra-hot ionized gases — plasmas, where fusion reactions occur. However, plasmas are unstable and prone to explosive phenomena known as edge localized modes (ELMs), which resemble solar flares, reports Interesting Engineering.
ELMs are magnetohydrodynamic (MHD) waves that cause energy and particle losses, potentially damaging the walls of reactors. In a new study, a team of scientists from the EUROfusion consortium has found that energetic ions, which are an important component of plasma, significantly affect the behavior of these waves.
Energetic particles interact with ELM waves, changing their spatiotemporal pattern. The study's lead author, Jesús José Domínguez-Palacios Durán, explained the phenomenon with an analogy: «It's like a surfer leaving a trail on a wave as he moves. An energetic particle interacts with an MHD wave, changing its structure».
The researchers conducted experiments at the ASDEX Upgrade tokamak in Germany and used advanced computer models from the MEGA code to analyze the interaction between ELM and energetic ions. They found that the interaction mechanism involves a resonant exchange of energy between particles and waves.
The results offer new approaches to controlling plasma destabilizations, opening the way to realizing nuclear fusion as a clean and virtually limitless energy source. Manipulating the population of energetic ions could make it possible to tame these «solar flares» in reactors and take an important step towards a sustainable future.