EXPERIMENTAL AND NUMERICAL-ANALYSIS OF A PLASMA COLLISION BY X-RAY SPECTROSCOPY AND IMAGING

The collision of two counter-streaming plasmas produced with laser-exploded thin foils has been diagnosed by x-ray imaging and spectroscopy. The time-history of the emission of the aluminium (1s(2)-1s3p) He beta line has been measured for different inter-target distances and laser intensities. Interpenetration has been observed for different plasma conditions by following the spatial extent of Mg and Al x-ray lines. Doppler broadening of the Al He beta line has been measured and is under analysis for ion temperature determination, taking into account reabsorption along the line of sight of the spectrograph. Comparison of the experimental data with a hydrodynamic code describing the interpenetrating plasmas and coupled with a radiative atomic package gives good overall agreement with the measurements of interpenetration and the history of the collision.