Nonlinear fluid simulation study of stimulated Raman and Brillouin scatterings in shock ignition

We developed a new nonlinear fluid laser-plasma-instability code (FLAME) using a multi-fluid plasma model combined with full electromagnetic wave equations. The completed one-dimensional version of FLAME was used to study laser- plasma instabilities in shock ignition. The simulations results showed that absolute stimulated Raman scattering (SRS) modes growing near the quartercritical surface were saturated by Langmuir-wave Decay Instabilities (LDI) and pump depletion. The ion-acoustic waves from LDI acted as seeds of Stimulated Brillouin Scattering, which displayed a bursting pattern and caused strong pump depletion. Re-scattering of SRS at the 1/16th-critical surface was also observed in a high temperature case. These results largely agreed with the corresponding Particle-in-Cell simulations. Published by AIP Publishing.