Evaluating the importance of Raman and Brillouin side scattering at ignition conditions

Abstract

A complete linear model for Raman and Brillouin side scattering is analyzed with infinite and finite boundary conditions. Analytic formulas of absolute thresholds and convective gains for side scatterings are derived when infinite boundary is assumed. Finite beam width introduces finite boundary conditions to the side scattering, which could influence both absolute thresholds and convective gains. Using these formulas and models, we have evaluated the importance of stimulated Raman side scattering and stimulated Brillouin side scattering at ignition conditions, including both direct drive and indirect drive. It shows that side scattering could be a possible way of scattering other than backscattering in several ignition situations.