LASER DRIVEN SHOCK WAVES IN PLEXIGLASS
The basic scheme: irradiating laser beam, solid plexiglass target and (Asterix III) iodine laser beam. Two cases were investigated: i) "out of focus" experiment with a 450 mum diameter of the irradiated area and a laser intensity of 1.4 x 10**14 W cm**-2, ii) "in focus" experiment with an 85 mum diameter of the irradiated area and a laser intensity of 3 x 10**15 W cm**-2. The shock front motion can be measured and compared with calculated shock wave trajectories: In the "out of focus" experiment it remains approximately planar for 10**-8 s. 1-D computer simulations agree quantitatively with the experiments and suggest a peak pressure of 6 Mbar during laser irradiation. The "in focus" experiments at 3 x 10**15 Wcm**-2 on a 85 mum diameter focal spot were simulated with the two-dimensional Eulerian MAGT code, (quasi-Lagrangian rezoning). A study about the influence of three parameters on the shock wave trajectory was made: i) equation of state; ii) diameter of the area of energy deposition; iii) and effective absorbed energy. The input data were the same as those used previously for simulation of thin foil acceleration experiments. Good agreement in both cases suggests that a quantitative prediction of laser-induced hydrodynamic motion is possible with such hydrocodes. For the nominal "in focus" conditions the code calculations give a peak pressure of 50 Mbar.
Bibliographic Reference: FOURTH APS CONFERENCE ON SHOCK WAVES IN CONDENSED MATTER, SPOKANE, WASHINGTON (USA), JULY 22-25, 1985 PUBLISHED IN SHOCK WAVES IN CONDENSED MATTER, 1986, PP. 535-539 PUBLISHED BY PLENUM PUBLISHING CORPORATION, NEW YORK (USA)
Record Number: 1989126019400 / Last updated on: 1989-03-01
Available languages: en