Measurement and interpretation of the spectrum of the triton burnup neutron emission from deuterium tokamak plasmas

Measurement and analysis of the energy distribution of the neutron emission from the nuclear burnup of tritons produced at 1 MeV in d+d --> t+p reactions are reported. The results refer to deuterium plasmas with a strongly pulsed neutron production attained with neutral beam heating in the JET tokamak representing both quasi-steady and transient plasma conditions. The measured triton produced neutron spectrum is described with reference to the triton slowing down behaviour in the plasma and pertinent parameter dependences as predicted with a time dependent model. The first study of the triton burnup neutron spectrum for both transient and quasi-steady-state plasma conditions is presented and a description based on classical confinement and slowing down of fast tritons is largely supported.