Low-converge ratio high-yield and large-scale implosions via high ρR + radiation trapping using Mo doped Be ablators (PSS)*

Beryllium ablators with inner layer doped with increasing Mo concentration towards the center can increase ρR with the benefit of radiation trapping. Configurations of this type of “high-ρR PSS” implosions with acceptable RT growth were reported.1 Based on this concept, we report new developments showing promises for achieving ignition that cannot be otherwise obtained using conventional approaches. (1) High-ρR and slow disassembly of the hotspot allow the use of DT liquid foam with high gas fill (1.5 – 2.0 mg/cc) and low-convergence ratio (< 20) implosions to deliver a few MJ in 2D. (2) Large-scale capsule (1500 m) gives high yield at lower implosion velocities since ρR increases with scale. However, YoC is lower which is apparently caused by the higher growth factor for large scales. Methods to improve the YoC will be discussed. (3) The high-ρR PSS allows the use of nominal-scale Be capsule with realistic drive to achieve ignition and high-yield in 2D while configurations using conventional Be ablators cannot. 1. D. Ho et al., APS-DPP PO6.00011(2018) and BO4.00010 (2019).