Summary
A new arXiv preprint revisits proton-boron (p-B11) fusion cross sections using updated experimental data and builds an analytical model spanning 0 to 10 MeV. The update highlights a higher-energy resonance near 4.7 MeV and recomputes thermonuclear reactivity, concluding that bremsstrahlung limits are less prohibitive under the paper's self-consistent thermal assumptions.
A 2025 EPJ A experiment measured p-B11 cross sections up to 4.73 MeV and reported a sharp rise near 4.5 MeV, reinforcing that the higher-energy region likely contains a meaningful resonance that shifts engineering requirements.
Signals for Investors
- Updated cross-section data narrows uncertainty for aneutronic fusion modeling, but the evidence remains preprint- and experiment-level rather than system-level validation.
- A resonance in the ~4-5 MeV range implies higher-energy beam or plasma requirements, raising the bar for accelerator, driver, and materials roadmaps.
- Near-term investable opportunities center on diagnostics, accelerator components, boron target supply chains, and high-temperature materials needed for p-B11 experiments.
What to Watch Next
Look for independent cross-section measurements around 4-6 MeV, peer review of the new analytical model, and any experimental energy-balance demonstrations that include realistic impurity and radiation transport. Track funding signals for dedicated p-B11 programs and facilities that can access the higher-energy regime.