Estimates of Intensity, Wavelength, and Bandwidth Scaling of Brillouin Backscatter

A simple nonlinear, one-dimensional spherical Brillouin-backscatter model adapted from kinetic simulations and Kruer's theory to a fluid code (LASNEX) is described. Laser absorption and Brillouin reflection are plotted for $0.265 \mu \mathrm{m}<{\lambda }_0<10.6\mathrm{} \mu \mathrm{m}$ and 3×${10}^{13}$ W/${\mathrm{cm}}^2$<laser intensity<3×${10}^{16}$ W/${\mathrm{cm}}^2$ on gold disks (pulse length=1 nsec) and the calculated absorption is compared with experiments. Kinetic simulations suggest methods of reducing the Brillouin backscatter, such as use of a wide bandwidth and multiline laser.