Observations of Multiple Nuclear Reaction Histories and Fuel-Ion Species Dynamics in Shock-Driven Inertial Confinement Fusion Implosions

Fuel-ion species dynamics in DT3He-gas-filled Inertial Confinement Fusion implosion is quantitatively assessed for the first time using simultaneously measured D3He and DT reaction histories. Here, these reaction histories are measured with the Particle X-ray Temporal Diagnostic, which captures the relative timing between different nuclear burns with unprecedented precision (~10 ps). The observed 50±10 ps earlier D3He reaction history timing (relative to DT) cannot be explained by average-ion hydrodynamic simulations, and is attributed to fuel-ion species separation between the D, T, and 3He ions during shock convergence and rebound. At the onset of the shock burn, inferred 3He/T fuel ratio in the burn region using the measured reaction histories is much higher as compared to the initial gas-fill ratio. As T and 3He have the same mass but different charge, these results indicate that the charge-to-mass ratio plays an important role in driving fuel-ion species separation during strong shock propagation.