JET DTE2 campaign: preparation, execution and selected highlights

Joelle Mailloux


Thursday, April 21, 2022



PSFC Seminars

Abstract: In 2021, high fusion power deuterium-tritium experiments (DTE2) were performed in JET for the first time since the 1997 D-T campaigns in TFTR and JET (DTE1). The preparation for DTE2 took place over many years, starting with the conception of the JET ITER-like wall (ILW: W divertor and Be main chamber). The preparation included several enhancements and dedicated experimental campaigns to expand the operational space in JET-ILW and prepare the plasmas required to exploit JET's currently unique tritium handling capabilities. DTE2 delivered record fusion energies and demonstrated the compatibility of sustained high performance D-T plasmas with the ILW. Unambiguous observations of alpha particles and of alpha-driven instabilities were obtained. Experiments designed to address specific physics questions provided several notable results, e.g. on plasma-wall interactions, L-H transition, energy confinement and pedestal behaviour with the ratio of T to D, where improved measurements compared to DTE1 will allow to better study the underlying physics. Efficient core heating and impurity control was observed with the Ion Cyclotron Radio Frequency schemes considered for ITER D-T operations: e.g. 3He minority heating, and a novel D-9Be-T three-ion scheme with the Be naturally present in the ILW. Plasmas with neon seeding for reducing divertor heat loads were performed for the first time in D-T. DTE2 provides a unique dataset for testing predictive capabilities and better prepare ITER fusion power operation.

Bio: After a BSc and a Master degree (nuclear physics) at the Université de Montréal and a two-year spell at the Atomic Energy Control Board in Ottawa, Joëlle Mailloux obtained a PhD at INRS-Énergie et Matériaux on the Lower Hybrid power losses in the SOL plasma of the Tokamak de Varennes, in 1997. She started a post-doctoral contract on Tore Supra at CEA-Cadarache in France that year, and from there moved to the United Kingdom in 1999 to work on JET, where she became a UKAEA employee and has stayed ever since. She was Microwave group leader and one of scientists leading JET plasma scenario development experiments until the end of 2016, when she became the EUROfusion JET Task Force Leader for the integrated operational scenarios, with the mandate to prepare and perform DTE2 with her co-TFLs and more than 350 scientists from 27 European research units, as well as several non-EU collaborators. Since the end of 2020, Joëlle is the UKAEA JET science programme leader and head of the JET science programme support office.