Correlating hot-electron preheat from the two-plasmon decay instability to ρR degradation for direct-drive implosions on OMEGA

Le résumé fourni par la source

Focused experiments were performed with the goal of isolating the impact of hot-electron preheat on compression in deuterium–tritium (DT) layered, direct-drive implosions on OMEGA. Preheat from the hot-electrons generated by two-plasmon–decay (TPD) activity was varied through the incident laser intensity, with the total preheat energy deposited into unablated DT fuel being inferred using hard x-ray measurements. Results show a clear correlation between the inferred preheat levels and ρR degradation that is consistent with a derived, 1D preheat model. A fit to the results also provides an estimated range of ρR degradation from non-preheat sources for the adiabat ≈5implosions used in this study. A follow-up study using targets containing Si-doped (5.5%) CH ablators (CHSi) demonstrated results consistent with mid-Z dopants mitigating TPD activity by showing these targets had almost no ρR degradation as the laser intensity was increased up to levels previously considered damaging.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.