Thomson scattering in the corona of laser-produced gold plasmas

Thomson scattering measurements of the electron temperature in laser-produced gold plasmas are presented. We irradiated a flat gold disk target with one laser beam of the Nova laser facility at an angle of 64° from the normal. A second laser beam probed the plasma at a distance of 500 μm with temporally resolved Thomson scattering. The electron temperature measurements are compared with hydrodynamic simulations using the code LASNEX for experiments applying smoothed and unsmoothed heater beams. In case of an unsmoothed heater beam the simulations predict temperatures which are about 40% higher than our measured data. Although the agreement is improved for a smoothed heater beam, discrepancies exist in the decay phase of the plasma. We discuss possible explanations for these observations.