In just two months, the European JET tokamak will begin experimenting with ''pure tritium'' plasmas (a first in the history of fusion research) before launching a deuterium-tritium campaign lasting until August 2021. (© EUROfusion)
On the technical side, the commissioning of a critical element for operating JET with tritium—the exhaust detritiation system—was completed during summer 2020. The expansion of the tritium boundary from the active gas handling system² to the JET torus and the neutral beam injection boxes was completed in September, and the commissioning of the heating neutral beams in tritium is now underway. I am particularly impressed by the way the team was able to make all of this progress in the context of a very challenging year, despite the interruption of our campaign in March 2020 due to COVID-19 and subsequent reductions in experimental days per week.
Xavier Litaudon was appointed head of ITER Physics at EUROfusion in 2014. As a young scientist, he was part of the 1997 deuterium-tritium campaign at JET. What he sees in the recent developments of fusion research worldwide is ''a collective result surpassing individual contributions''—something that provides him with ''a great feeling of happiness.'' (© EUROfusion)
Indeed, the physics knowledge of D-T plasmas is still limited and ITER will be essential to making further progress. We have to disentangle all kinds of physics processes. For instance, the change of the fuel mass from deuterium to a mixture of deuterium-tritium, or processes related to the alpha heating effects by the reaction product of the D-T fusion reaction. JET has developed a scientific program where similar discharges in D-D, T-T and D-T will be performed, compared and simulated with the models and codes used to predict ITER performance. If new physics processes are discovered they will be implemented in our modeling suite and the simulation will be compared to the latest experimental results to shed light on the physics of the future burning plasma. This effort will contribute to optimizing the transition from D-D to D-T plasma operation in ITER.
This stunning illustration is a computer-generated image of JET; it is what you would see if you could see all the way through to the hot plasma fuel inside. The models, based on real design data from JET, demonstrate a new simulation tool known as CHERAB, developed by the Culham Centre for Fusion Energy. CHERAB aims to speed up the generation of accurate data from fusion devices. (© CCFE)