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arXiv · 2409.12644

Analysis of non-diffusive avalanche transport of energetic particles

Nakia Carlevaro·Matteo V. Falessi·Giovanni Montani·Philipp Lauber
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Abstract

The dynamics of energetic particles (EPs) interacting with Alfv\'en eigenmodes (AEs) for the ITER 15MA baseline scenario was described using a reduced 1D model in [Carlevaro et al. PPCF 64, 035010 (2022)], and successfully tested against nonlinear wave-particle simulations. In this paper, we introduce a detailed phase-space and statistical analysis of this case to characterize the emerging EP transport regimes. Deviations from pure diffusive dynamics are quantitatively addressed, indicating the limitations of standard quasi-linear descriptions. The phase space diagnostics introduced allows to describe the emergence of a very complex dynamics of overlapping resonances and substructure formation, reinforcing the evidence of non-diffusive domino-like AEs.

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Nakia Carlevaro, Matteo V. Falessi, Giovanni Montani, Philipp Lauber. 2024-09-19. Analysis of non-diffusive avalanche transport of energetic particles. https://doi.org/10.1016/j.physd.2026.135286

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