Mode structure measurements of ion cyclotron emission and sub-cyclotron modes on DIII-D

GH DeGrandchamp, JB Lestz, MA Van Zeeland… - Nuclear …, 2022 - iopscience.iop.org
We report mode structure measurements of coherent ion cyclotron emission (ICE) and sub-
cyclotron modes on DIII-D. Through a dedicated experiment, we aimed to characterize a …

Compressional Alfvén eigenmodes excited by runaway electrons

C Liu, DP Brennan, A Lvovskiy, C Paz-Soldan… - Nuclear …, 2021 - iopscience.iop.org
Compressional Alfvén eigenmodes (CAEs) driven by energetic ions have been observed in
magnetic fusion experiments. In this paper, we show that the modes can also be driven by …

Stabilization of Alfvén eigenmodes in DIII-D via controlled energetic ion density ramp and validation of theory and simulations

SX Tang, TA Carter, NA Crocker, WW Heidbrink… - Physical Review Letters, 2021 - APS
Fast-ion driven Alfvén waves with frequency close to the ion cyclotron frequency (f= 0.58 fci)
excited by energetic ions from a neutral beam are stabilized via a controlled energetic ion …

NSTX-U theory, modeling and analysis results

W Guttenfelder, DJ Battaglia, E Belova, N Bertelli… - Nuclear …, 2022 - iopscience.iop.org
The mission of the low aspect ratio spherical tokamak NSTX-U is to advance the physics
basis and technical solutions required for optimizing the configuration of next-step steady …

Analysis of high frequency Alfvén eigenmodes observed in ASDEX Upgrade plasmas in the presence of RF-accelerated NBI ions

R Ochoukov, S Sipilä, R Bilato, V Bobkov… - Nuclear …, 2023 - iopscience.iop.org
High frequency Alfvén eigenmodes in the ion cyclotron frequency range are actively
researched on the ASDEX Upgrade tokamak (AUG). The general properties of this particular …

Impact of ICRF fast-ions on core turbulence and MHD activity in ASDEX upgrade

A Bilato, C Angioni, AB Navarro, V Bobkov… - AIP Conference …, 2023 - pubs.aip.org
Experiments in various tokamaks and their analysis identify the fast ions (FI) generated by
NBI and/or ICRF heating as one of the main causes of the observed improvement in core …

Hybrid simulations of sub-cyclotron compressional and global Alfvén eigenmode stability in spherical tokamaks

JB Lestz, EV Belova, NN Gorelenkov - Nuclear Fusion, 2021 - iopscience.iop.org
A comprehensive numerical study has been conducted in order to investigate the stability of
beam-driven, sub-cyclotron-frequency compressional Alfvén eigenmodes (CAEs) and global …

Observation of bi-directional global Alfvén eigenmodes in the MAST-U tokamak

MB Dreval, HJC Oliver, SE Sharapov… - Nuclear …, 2024 - iopscience.iop.org
The first observations and classification of deuterium beam-driven sub-cyclotron frequency
range Alfvén eigenmodes (AEs) are presented for the MAST-Upgrade tokamak. Sets of …

Application of simulations and theory of sub-cyclotron frequency modes to DIII-D

EV Belova, NA Crocker, JB Lestz… - Nuclear Fusion, 2022 - iopscience.iop.org
Theoretical and numerical study of Alfvén eigenmodes (AEs) in the sub-cyclotron frequency
range explains the observed frequency scaling with beam parameters in experiments across …

[HTML][HTML] Analytic stability boundaries for compressional and global Alfvén eigenmodes driven by fast ions. II. Interaction via Landau resonance

JB Lestz, NN Gorelenkov, EV Belova, SX Tang… - Physics of …, 2020 - pubs.aip.org
Conditions for net fast ion drive are derived for beam-driven, co-propagating, sub-cyclotron
compressional (CAE) and global (GAE) Alfvén eigenmodes driven by the Landau resonance …