Predictions of improved confinement in SPARC via energetic particle turbulence stabilization
Abstract
The recent progress in high-temperature superconductor technologies has led to the design and construction of SPARC, a compact tokamak device expected to reach plasma breakeven with up to MW of external ion cyclotron resonant heating (ICRH) power. This manuscript presents local (flux-tube) and radially global gyrokinetic GENE (Jenko et al 2000 Phys. Plasmas {\bf 7} 1904) simulations for a reduced-field and current H-mode SPARC scenario showing that supra-thermal particles - generated via ICRH - strongly suppress ion-scale turbulent transport by triggering a fast ion-induced anomalous transport barrier (F-ATB). The trigger mechanism is identified as a wave-particle resonant interaction between the fast particle population and plasma micro-instabilities (Di Siena et al 2021 Phys. Rev. Lett. {\bf 125} 025002). By performing a series of global simulations employing different profiles for the thermal ions, we show that the fusion gain of this SPARC scenario could be substantially enhanced up to by exploiting this fast ion stabilizing mechanism. A study is also presented to further optimize the energetic particle profiles, thus possibly leading experimentally to an even more significant fusion gain.
Keywords
Cite
@article{arxiv.2210.11816,
title = {Predictions of improved confinement in SPARC via energetic particle turbulence stabilization},
author = {A. Di Siena and P. Rodriguez-Fernandez and N. T. Howard and A. Banon Navarro and R. Bilato and T. Goerler and 1 E. Poli and G. Merlo and J. Wrigh and M. Greenwald and F. Jenko},
journal= {arXiv preprint arXiv:2210.11816},
year = {2023}
}