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

Recent implosion experiments performed at the OMEGA laser facility reported by Casey et al.[1], displayed an anomalously low dd proton yield and a high tt neutron yield as compared to dt fusion reactions, explained as a stratification of the fuel in the implosion core. We suggest that in the com- pression stage the fuel is out of equilibrium. Ions are inward accelerated to a velocity v0 independent on the particle type. Yield ratios are simply given by the ratios of fusion cross-sections obtained at the same velocity. A 'Hubble' type model gives also a reasonable description of the data. These considerations might be relevant for implosion experiments at the National Ignition Facility as well.