Speaker: Yong-Su Na, Department of Nuclear Engineering, Seoul National University, Seoul, Republic of Korea

Title: "A new regime to "FIRE" fusion plasmas toward long sustained and high-performance reactor conditions"

Abstract: We report a new advanced tokamak operation mode, the Fast Ion Regulated Enhancement (FIRE) mode, established in KSTAR, which is characterized by a sustainable ion Internal Transport Barrier (I TB) for a long duration of about a few ten seconds and low divertor heat load attributed to the absen ce of Edge-Localized Modes (ELMs). To access the FIRE mode, low density and single null configurat ions, coupled with moderate Neutral Beam Injection (NBI) heating power, have been used to form and sustain ITB by preventing H-mode transition. The origin of the high confinement of this scenario was investigated by power balance and gyrokinetic analyses revealing the critical role of fast ions in enhanc ing energy confinement. Additionally, predictive modelling has been conducted with TRIASSIC for a FI RE mode discharge to set a basis for the projection of FIRE mode to future devices. (Yong-Su Na, on behalf of the KSTAR teamteam)

Bio: Dr. Yong-Su Na is a full Professor in the Department of Nuclear Engineering in the  College of Engineering at Seoul National University, Korea. He is currently a Visiting Research Scholar at Princeton University's Princeton Plasma Physics Laboratory. He received his Dr.rer.nat in Plasma Physics at the Technische Universität München in 2003 and then went on to work as a researcher at Max-Planck-Institut für Plasmaphysik, Germany (2003-2005); the National Fusion Research Center, Korea (2005-2006), and the National Fusion Research Institute, Korea (2006-2008). He joined the faculty at the University of Science and Technology, Korea, as an assistant professor in 2007 and was named a full professor in 2017. He began working as a Visiting Research Scholar at Princeton University's Princeton Plasma Physics Laboratory in 2015 and has continued that collaboration since that time.

Prof. Na has served as a committee member for the Division of Plasma Physics in the Korean Physical Society since 2010; was named the Deputy leader of the KSTAR Advanced Operation Scenario Working Group in 2017; as named a member of the Young Korean Academy of Science and Technology (Y-KAST) in 2018; was named Director of the Tokamak Research Center for Current drive and Heating (TORCCH) in 2021; was named a member of the ITER Science and Technology Advisory Committee in 2022; served on the Programme Committee for the 2022 H-mode Workshop; has been an Editorial Board Member of the Journal of the Korean Physical Society since 2023; and has served as a Coordinator for the Burning Plasma Working Group, Korean DEMO Design TF since 2023.

This talk will be offered in a hybrid format. If you wish to participate remotely, please send an email to [email protected].