19th Technical Meeting on Energetic Particles in Magnetic Confinement Systems

Development of an action-angle quasilinear theory for wave-particle interactions in stellarators

Not scheduled

20m

Beaulieu Congress and Exhibition Center (Lausanne, Switzerland)

Poster Poster session I

Speaker

Avigdor Veksler (Columbia University)

Description

Understanding the interactions between the energetic particle (EP) distribution function with waves is critical for burning plasma operation in future reactor-scale stellarators. We develop a quasilinear theory for nonlinear alpha particle-AE interactions in stellarators, building on a resonance-broadened quasilinear model for tokamaks [1] in action-angle coordinates. Action-angle coordinates are developed for quasisymmetric and omnigenous stellarators. The predicted diffusion of the alpha particle distribution function with respect to particle constants of motion (actions) under the influence of shear Alfvén waves is computed and validated with particle tracing simulations in the open-source FIRM3d code [2], where the diffusion coefficient is learned from data using the SINDy formalism [3].

[1] N.N. Gorelenkov et al 2018 Nucl. Fusion 58(8)
[2] E. Paul et al 2026 arXiv preprint arXiv:2605.16734.
[3] A. Kaptanoglu et al 2022 Journal of Open Source Software, 7(69)