Proton–Boron-11 (p–¹¹B)

The truly aneutronic reaction — a long-term research endpoint, not the Kronos baseline.

Proton–boron-11 fusion produces only charged particles, making it the truly aneutronic reaction. It requires extreme temperatures and remains a research destination. Kronos frames it as a far-future endpoint, not its commercial baseline — and never conflates its low-neutron D–³He burner with it.