Saved in:
Bibliographic Details
Main Authors: Wright, Adelle M., Faber, Benjamin J.
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2512.22355
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917172087881728
author Wright, Adelle M.
Faber, Benjamin J.
author_facet Wright, Adelle M.
Faber, Benjamin J.
contents Maximising particle and energy confinement is crucial for achieving the sustained burning plasma conditions necessary to realise fusion energy. For stellarator reactors, one proposed strategy for avoiding destructive instabilities is to operate at high-field but low(er) plasma pressure. In this work, we investigate the accessibility of such a reactor-relevant low-beta regime in a reactor-scale quasi-axisymmetric stellarator using state-of-the-art high-fidelity macro- and microscopic simulation tools. We consider a configuration with a flattened core pressure profile and favourable properties from the macroscopic and neoclassical perspectives. By contrast, linear and nonlinear calculations with the GENE code show an abrupt transition to a regime of highly deleterious transport at low (local) plasma beta. We describe the characterisation of these transport regimes as well as the confinement transition. We discuss the implications broadly for stellarator optimisation and highlight the impact on quasi-symmetric stellarator design strategies.
format Preprint
id arxiv_https___arxiv_org_abs_2512_22355
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle On the accessibility of stable reactor operating regimes in quasi-symmetric stellarators
Wright, Adelle M.
Faber, Benjamin J.
Plasma Physics
Maximising particle and energy confinement is crucial for achieving the sustained burning plasma conditions necessary to realise fusion energy. For stellarator reactors, one proposed strategy for avoiding destructive instabilities is to operate at high-field but low(er) plasma pressure. In this work, we investigate the accessibility of such a reactor-relevant low-beta regime in a reactor-scale quasi-axisymmetric stellarator using state-of-the-art high-fidelity macro- and microscopic simulation tools. We consider a configuration with a flattened core pressure profile and favourable properties from the macroscopic and neoclassical perspectives. By contrast, linear and nonlinear calculations with the GENE code show an abrupt transition to a regime of highly deleterious transport at low (local) plasma beta. We describe the characterisation of these transport regimes as well as the confinement transition. We discuss the implications broadly for stellarator optimisation and highlight the impact on quasi-symmetric stellarator design strategies.
title On the accessibility of stable reactor operating regimes in quasi-symmetric stellarators
topic Plasma Physics
url https://arxiv.org/abs/2512.22355