Thomson-scattering measurements of high electron temperature hohlraum plasmas for laser-plasma interaction studies

Abstract

Accurate measurements of the plasma conditions in laser-produced high-temperature plasmas have been achieved using the recently activated 4ω Thomson-scattering diagnostic at the Omega Laser Facility, Soures et al., Laser Part. Beams 11 (1993). These diagnostic measurements were performed in a new hohlraum target platform that will be used to study laser-plasma interaction in a strongly damped regime comparable to those occurring in indirect drive inertial confinement fusion plasmas. The Thomson-scattering spectra show the collective ion-acoustic features that fit the theory for two ion species plasmas allowing us to accurately and independently determine both the electron and ion temperatures. The electron temperature was found to range from 2to4keV as the total heater beam energy deposited into the hohlraum was increased from 8to17kJ. The results are compared to 2D hydrodynamic simulations using flux limited diffusion and nonlocal heat flux models. The target platform presented provides a novel test bed to investigate laser-plasma interaction physics in the strongly damped backscatter regime.