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Question
Is Kronos fusion aneutronic?
No — Kronos is 'low-neutron,' not aneutronic. The D–³He primary reaction is aneutronic, but side D–D reactions make some neutrons. Only the gated p–¹¹B endpoint is truly aneutronic.
Kronos deliberately says low-neutron, not aneutronic, for the commercial machine — a precision that is part of its show-your-work discipline. The full explanation is on does D–³He produce neutrons?
The genuinely aneutronic p–¹¹B reaction is treated as a gated endpoint, not a headline.
Questions & answers
Is Kronos fusion aneutronic?
No, and Kronos is careful about the word. The primary D–³He reaction is aneutronic, but any real D–³He plasma also runs side deuterium–deuterium reactions, one branch of which emits a neutron. So the plant is low-neutron — a neutron fraction around 5.25%, roughly 25× below D–T — not neutron-free.
Is any Kronos fuel truly aneutronic?
Only the proton–boron-11 (p–¹¹B) endpoint, which produces no neutrons from its primary reaction. That is the one place Kronos uses the word 'aneutronic,' and it is a gated research endpoint at the far end of the fuel roadmap — not the commercial baseline.
Why does the distinction matter?
Because overstating neutron performance is a common way fusion claims lose credibility. 'Low-neutron' is accurate and still a major advantage — it's what enables direct energy conversion and drives down activation, shielding, and cost.