Evidence for Stratification of Deuterium-Tritium Fuel in Inertial Confinement Fusion Implosions

Measurements of the D(d, p)T (dd) and T(t, 2n)He-4 (tt) reaction yields have been compared with those of the D(t, n)He-4 (dt) reaction yield, using deuterium-tritium gas-filled inertial confinement fusion capsule implosions. In these experiments, carried out on the OMEGA laser, absolute spectral measurements of dd protons and tt neutrons were obtained. From these measurements, it was concluded that the dd yield is anomalously low and the tt yield is anomalously high relative to the dt yield, an observation that we conjecture to be caused by a stratification of the fuel in the implosion core. This effect may be present in ignition experiments planned on the National Ignition Facility.