neutron, 14 MeV is the fast neutron carrying most of the energy released by 📝deuterium-tritium 📝fusion — a particle that, having no charge, escapes the confining magnetic field and deposits its energy in the blanket.
The near-neighbor comparison is with the reaction's other product. Each 📝D-T reaction releases 17.6 MeV split by momentum conservation into a 3.5 MeV 📝alpha particle and a 14.1 MeV neutron: the charged alpha stays trapped in the field and heats the 📝plasma, while the neutral neutron flies straight out. That division of labor defines a fusion plant's architecture — the alpha keeps the fire burning, and the neutron, carrying roughly 80 percent of the energy, delivers the product. The 📝blanket is where the neutron's journey ends, its kinetic energy becoming heat for the power cycle and its capture on 📝lithium breeding fresh 📝tritium.
The energy also distinguishes fusion neutrons from fission's, which average around 2 MeV. At 14 MeV a neutron penetrates deeper, displaces more atoms from their lattice sites, and drives threshold reactions — including the (n,2n) multiplication that breeding exploits — that slower neutrons cannot. The same hardness makes materials qualification a central fusion challenge: no operating facility yet produces a power-plant-relevant flux of 14 MeV neutrons for testing, so the world's data on how materials endure them remains a gap the first generation of plants will help close.