Investigating long-duration plasma operation with the international multi-machine CICLOP database

Abstract Combined high-fusion performance and long-pulse operation is one of the key integration challenges for fusion energy development in magnetic devices. Addressing these challenges requires an integrated vision of physics and engineering aspects with the purpose of simultaneously increasing time duration and fusion performance. Since the previous 2023 IAEA Fusion Energy Conference (FEC), significant progresses have been made in tokamaks and stellarators including very recent achievement in duration and/or performance. These progresses are reviewed by analysing the experimental data provided by 10 tokamaks and two stellarators. The published database (Litaudon et al 2024 Nucl. Fusion 64 015001), which initially included data up to January 2022, has been significantly updated for the 2025 IAEA FEC to incorporate the latest 2023–2025 experiments (up to May 2025) including recent records performance with new entries provided by DIII-D, EAST, JET, KSTAR, WEST, and W7-X. The update dataset has been gathered and coordination have been provided by the IEA-IAEA international CICLOP group (Coordination on International Challenges on Long duration OPeration). An overview of the recent progress toward long pulse operation analysing the CICLOP database is provided in this publication.