Tritium Particle Transport Experiments on TFTR during D-T Operation

The $t\left(d,n\right)\alpha$ and $d(d,n{)}^3\mathrm{He}$ neutron emissivity profiles are measured in a deuterium neutral-beam–heated plasma where a small amount of tritium (T) gas has been puffed. The tritium density is inferred from the neutron emissivities, and transport coefficients ( $D,V$) are determined. The particle diffusivities of T and ${}^4$He and the thermal diffusivity are similar in magnitude and profile shape. The convective velocity is small for $r/a<\mathrm{}0.6\mathrm{}$, and is anomalous for $r/a>\mathrm{}0.6\mathrm{}$. These are the first measurements of $D$ and $V$ for a hydrogen isotope in a tokamak plasma.