Influence of mass ablation on ignition and burn propagation in layered implosions and implications for capsule design*

Ignition in layered ICF implosions involves balancing energy losses into the hot spot from radiation and thermal conduction with energy from PdV work, fusion reaction products, and the enthalpy associated with ablation of fuel into the hot spot (which can lead to 4x larger ablative inflows than previous estimates). The authors have shown analytically and computationally that the rate of mass ablation depends upon the thermodynamic state of the dense fuel, which ultimately governs mass inflow, controls hot spot temperature, and modifies the burn propagation dynamics.* A recent study incorporating this new understanding points to novel design paths for improved burn performance in layered implosions. This paper will discuss some of these new ideas as well as some of the associated design tradeoffs.

*W. S. Daughton, B. J. Albright, S. M. Finnegan, Brian M. Haines, J. L., Kline, J. P. Sauppe, and J. M. Smidt, Phys. Plasmas 30, 012704 (2023).