14 MeV Fusion Neutrons
Each deuterium-tritium fusion releases a 14 MeV neutron; these high-energy neutrons are a tool for materials testing that few other sources can match.
- Neutron energy
- ~14.1 MeV
- Source
- D-T fusion
- Breeder power
- 85.0 MW
- Use class
- Materials testing
A distinctive neutron
A deuterium-tritium fusion reaction releases a neutron carrying about 14.1 MeV of kinetic energy — far more than the neutrons typical of fission reactors. That high energy makes fusion neutrons uniquely suited to reproducing the kind of damage that materials would experience inside a fusion device, and to certain testing and analysis tasks.
The breeder (Hyperion) is a deuterium-tritium spherical tokamak producing 85.0 MW of fusion power in the design set. Alongside tritium and helium-3, its 14 MeV neutron flux is itself a strategic output: a domestic source of fusion-spectrum neutrons for materials qualification and testing.
Why 14 MeV is special
- High energy: reproduces fusion-relevant damage mechanisms.
- Distinct spectrum: differs from fission neutrons in the damage it causes.
- Enables transmutation and activation studies at fusion energies.
- Domestic fusion-spectrum sources are historically scarce.
Energy carried by the neutron
A detail that gives fusion neutrons their character is where the reaction energy goes. In the deuterium-tritium reaction, most of the released energy is carried off by the neutron as kinetic energy, which is why it emerges near 14 MeV rather than at the lower energies typical of fission. That high energy is exactly what makes the neutron useful for reproducing fusion-relevant damage and for opening reaction channels that softer neutrons cannot reach. The breeder's neutron output is therefore not a by-product to be shielded away but a strategic capability in its own right.
The pages in this cluster cover the fusion neutron spectrum, damage metrics, materials testing, and the long-standing gap in fusion-relevant irradiation capability. All neutron-service figures are computed design targets pending FOAK.