GENERATION OF HOT AND DENSE-PLASMAS IN LASER ACCELERATED COLLIDING FOIL SYSTEMS

We create hot (T-e > 200 eV) and dense (N-e > 10(23) cm(-3)) plasmas i n the colliding zone of two thin foils accelerated by two laser beams of the LULI facilities. Three spectroscopic diagnostics (two 1D space- resolved spectrographs and a 2D monochromatic imaging) are used to dri ve the efficiency of the compression. We show that 2D effects are impo rtant. Realistic simulations of these experiments must be done, taking into account the inhomogeneity of the laser intensity in the focal sp ot, the foil distorsion, the plasma lateral expansion, and the lateral thermal conduction. Two-dimensional LASNEX code results are in good a greement with our experimental results. The optimized compressed plasm as generated are favorable for the exhibition of dense plasma effects due to molecular formations, and they reproduce in laboratory some ast rophysical situations.