Matter and Radiation at Extremes, Vol. 4, Issue 5, 055401 (2019)
Fuel-ion diffusion in shock-driven inertial confinement fusion implosions
Hong Sio1,a), Chikang Li1, Cody E. Parker1, Brandon Lahmann1, Ari Le2, Stefano Atzeni3, and Richard D. Petrasso1
- 1Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- 2Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
- 3Dipartimento SBAI, Università degli Studi di Roma “La Sapienza,” Via Antonio Scarpa 14, 00161, Roma, Italy
The impact of fuel-ion diffusion in inertial confinement fusion implosions is assessed using nuclear reaction yield ratios and reaction histories. In T3He-gas-filled (with trace D) shock-driven implosions, the observed TT/T3He yield ratio is ∼2× lower than expected from temperature scaling. In D3He-gas-filled (with trace T) shock-driven implosions, the timing of the D3He reaction history is ∼50 ps earlier than those of the DT reaction histories, and average-ion hydrodynamic simulations cannot reconcile this timing difference. Both experimental observations are consistent with reduced T ions in the burn region as predicted by multi-ion diffusion theory and particle-in-cell simulations.