Integrated Modeling Shows ARC Fusion Reactor Can Achieve Near-Gigawatt Power While Protecting Divertor
Researchers have published integrated modeling results for the ARC compact fusion reactor, showing that fusion power approaching one gigawatt can be achieved while keeping divertor temperatures safely below 2 eV using argon impurity seeding. The study self-consistently modeled impurity radiation and density profiles across the plasma core and edge, finding that argon seeding outperforms neon in both fusion output and H-mode stability. These findings strengthen the case that ARC's high-performance operating scenarios are compatible with the divertor protection requirements needed for a viable fusion power plant.
A new preprint on arXiv presents core-edge integrated modeling of the ARC compact tokamak, assessing whether high-performance H-mode plasmas can be sustained alongside divertor detachment conditions necessary to protect plasma-facing components. The modeling demonstrates that fusion power levels of 750–1000 MW are achievable with argon seeding, with performance showing strong sensitivity to separatrix density and weaker dependence on enrichment factor and pedestal density. Argon seeding consistently enabled H-mode access and detached divertor operation, while neon seeding produced lower fusion power (600–850 MW) and less reliable H-mode access due to excessive core impurity accumulation. A small tungsten impurity peaking was identified, with the effect diminishing at higher effective charge (Zeff). Sensitivity analyses incorporating reduced momentum transport modeling and neoclassical impurity transport confirmed the robustness of the overall conclusions. The results collectively support the viability of ARC operating in a regime that simultaneously achieves high fusion performance and adequate divertor heat exhaust management.
What's missing
The study is a preprint and has not yet undergone peer review. ARC itself has not yet been built, so all results are projections. Long-pulse or steady-state sustainability of the detached divertor conditions is not addressed.
What different sources said
- arXiv physicsCenter
Core-edge integrated modeling of ARC: on the effect of impurity transport and detachment conditions
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