Historical research guide · 0034 · 2025
Improvements in and relating to isotope production
Tom WALLACE-SMITH · Thomas Peter Jackson HAYWOOD · Robert ANNEWANDTER · Madeleine Serena WOODWARD · Astral Neutronics Ltd
In one minute
Astral Neutronics — the company behind Astral Systems in Bristol — filed this application to make the isotopes nuclear medicine runs on without a fission reactor and without a particle accelerator. Tom Wallace-Smith and his co-inventors describe a compact fusion neutron source, then use its neutrons to transmute ordinary target metals into Actinium-225, Lead-212, Terbium-161, Gold-199, Scandium-47, Copper-64, Copper-67, Bromine-77 and Yttrium-90. The reactor is the interesting part. It is an inertial electrostatic confinement machine whose electrodes carry a metal lattice deliberately loaded with deuterium, so fusion happens twice over: in the plasma, and inside the solid, where the metal’s own electrons screen the electrical repulsion between nuclei — lattice confinement fusion. Filling the chamber with tritium while the lattice holds deuterium tips the reaction towards deuterium–tritium, and the reported spectrum comes out dominated by 12 to 16 MeV neutrons. Modelled onto radium-226 targets, that spectrum leaves under 0.01 per cent of the unwanted actinium-227, where a fission reactor’s neutrons make more contaminant than product.
Connection
Chapter 12 argues that screening the Coulomb barrier inside a metal lattice is the first practical door the vacuum thesis opens; this is that mechanism written up as a commercial product — a named reactor, a measured neutron spectrum, a purity figure, and a machine small enough to stand next to the hospital that uses the isotopes.
From the source
Electron screening inside a conductive metal lattice neutralises the positive charge of fusible ions held in it, so fusion proceeds at lower required energy and at enhanced rates; the application cites Prados-Estevez, Subashiev and Nee on the top ten valence electrons nullifying the Coulomb potential and raising the fusion cross-section.Detailed description — lattice confinement fusion
A multi-state fusion reactor runs plasma fusion and lattice confinement fusion together: an inertial electrostatic confinement vessel with concentric anode and cathode, at least one electrode carrying a surface deliberately enriched to at least 100 ppm deuterium or tritium by atomic percentage, in metals with an electron screening potential of at least 200 eV — titanium, zirconium, palladium, erbium or CVD diamond.Summary of the invention — nuclear fusion reactor
Loading the chamber gas with tritium while the electrode lattice holds deuterium — or the reverse — favours deuterium–tritium fusion over deuterium–deuterium and tritium–tritium, and the reported spectra carry at least 50 per cent, and in the better cases 80 to 85 per cent, of their neutrons in the 12 to 16 MeV band.Detailed description, Figure 7 and Table 1
MCNP6.2 modelling of radium-226 irradiation puts actinium-227 contamination below 0.01 per cent of the actinium-225 produced at target thicknesses up to 10 mm, and as low as 0.0047 per cent with a thinner target, against roughly 0.5 per cent for a linear-accelerator spectrum and, for the BR2 fission-reactor spectrum, more actinium-227 than actinium-225.Results — Figures 8 and 9
The same irradiation yields useful quantities of Lead-212 alongside the Actinium-225, giving a single target a route to two clinically useful isotopes.Results — modelling of radium-226 irradiation
Because damage is spread across the whole anode and cathode surface rather than concentrated on a solid target, the inventors expect a mean time between failures of 20,000 hours or more, against the 4,000-hour best guaranteed lifetime of a sealed-tube neutron generator.Detailed description — reactor lifetime and durability
The way in
https://patents.google.com/patent/WO2025253127A1/enHow to cite it
Tom WALLACE-SMITH, Thomas Peter Jackson HAYWOOD, Robert ANNEWANDTER, Madeleine Serena WOODWARD, Astral Neutronics Ltd (2025) Improvements in and relating to isotope production WO2025253127A1